UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

for the fiscal year ended January 31, 2008,

or

Commission file number 1-6991.

WAL-MART STORES, INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (479) 273-4000

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  x    No  ¨

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Exchange Act.    Yes  ¨     No  x

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for at least the past 90 days.    Yes  x    No  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  x

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See definition of “accelerated filer,” large accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ¨     No  x

As of July 31, 2007, the aggregate market value of the voting common stock of the registrant held by non-affiliates of the registrant, based on the closing sale price of those shares on the New York Stock Exchange reported on July 31, 2007, was $108,832,733,376. For the purposes of this disclosure only, the registrant has assumed that its directors, executive officers and beneficial owners of 5% or more of the registrant’s common stock are the affiliates of the registrant.

The registrant had 3,954,458,057 shares of common stock outstanding as of March 21, 2008.

DOCUMENTS INCORPORATED BY REFERENCE

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS AND INFORMATION

This Annual Report on Form 10-K, the other reports, statements, and information that Wal-Mart Stores, Inc. (together with its subsidiaries hereinafter referred to as “we,” “Wal-Mart” or the “Company”) have previously filed or that we may subsequently file with the Securities and Exchange Commission (“SEC”) and public announcements that we have previously made or may subsequently make include, may include, or may incorporate by reference certain statements that may be deemed to be “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, and that are intended to enjoy the protection of the safe harbor for forward-looking statements provided by that Act. The forward-looking statements included or incorporated by reference in this Form 10-K and that are or may be included or incorporated by reference in those reports, statements, information, and announcements address activities, events or developments that we expect or anticipate will or may occur in the future, including or relating, but not limited to, the amount, nature and allocation of future capital expenditures, opening of additional stores and clubs in the United States and additional units in the other countries in which we operate, conversion of discount stores into supercenters, relocations of existing units, remodeling of or special projects at existing units, expansion and other development trends of the retail industry, our ability to integrate newly acquired operations into our existing operations, our business strategy, our pricing strategy, our cost of goods, our inventory levels, the anticipated success and timing of various operating initiatives, our ability to increase our market share, our financing strategy, expansion and growth of our business, changes in our operations, including the mix of products sold, our liquidity and ability to access the capital markets, the effect of economic developments on our customers and our operations, our anticipated earnings per share for certain periods, our annual tax rate, our anticipated levels of change in comparable store sales from one period to another period and other similar matters. Forward-looking statements are often identified by the use of words or phrases such as “anticipate,” “believe,” “could occur,” “could result,” “estimate,” “expect,” “forecast,” “plan,” “projected,” “will be,” “will continue,” “will change,” “will decrease” and “will increase.” Although we believe the expectations expressed in the forward-looking statements included in this Form 10-K and such reports, statements, information and announcements are based or will be based on reasonable assumptions within the bounds of our knowledge of our business, a number of factors could cause our actual results to differ materially from those expressed or implied in any forward-looking statements, whether oral or written, made by us or on our behalf. Many of these factors have previously been identified in filings or statements made by us or on our behalf.

Our business operations are subject to numerous factors outside our control. Any one, or a combination, of these factors could materially affect our financial performance, business operations, business strategy, plans, goals and objectives. These factors include, but are not limited to: general economic conditions, the cost of goods, consumer credit availability, information security costs, labor costs, transportation costs, the cost of diesel fuel, gasoline, natural gas and electricity, the cost of healthcare benefits, our insurance costs, the cost of construction materials, availability of acceptable building sites for new stores, clubs and other formats, competitive pressures, inflation, accident-related costs, consumer buying patterns and debt levels, weather patterns, catastrophic events, transport of goods from foreign suppliers, currency exchange fluctuations, trade restrictions, changes in tariff and freight rates, adoption of or changes in tax and other laws and regulations that affect our business, the outcome of legal proceedings to which we are a party, unemployment levels, interest rate fluctuations, changes in employment legislation and other capital market, economic and geo-political conditions and events. Moreover, we typically earn a disproportionate part of our annual operating income in the fourth quarter as a result of the seasonal buying patterns. Those buying patterns are difficult to forecast with certainty. The foregoing list of factors that may affect our performance is not exclusive. Other factors and unanticipated events could adversely affect our business operations and financial performance. Our business operations, results of operations, financial condition and liquidity are subject to other risk factors, which we discuss below under the caption “Item 1A. Risk Factors.” Readers are urged to consider all of these risks, uncertainties and other factors carefully in evaluating the forward-looking statements. Forward-looking statements that we make or that are made by others on our behalf are based on a knowledge of our business and the environment in which we operate, but because of the factors described and listed above, as well as other factors, or as a result of changes in facts, assumptions not being realized or other circumstances, actual results may differ materially from those contemplated in the forward-looking statements. Consequently, this cautionary statement qualifies all of the forward-looking statements we make herein and that are incorporated by reference herein. We cannot assure the reader that the results or developments expected or anticipated by us will be realized or, even if substantially realized, that those results or developments will result in the expected consequences for us or affect us, our business, our operations or our operating results in the way we expect. We caution readers not to place undue reliance on such forward-looking statements, which speak only as of their dates. We undertake no obligation to update any of the forward-looking statements to reflect subsequent events or circumstances except to the extent required by applicable law.

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WAL-MART STORES, INC.

ANNUAL REPORT ON FORM 10-K

FOR THE FISCAL YEAR ENDED JANUARY 31, 2008

PART I

General

Wal-Mart Stores, Inc. (“Wal-Mart,” the “Company” or “we”) operates retail stores in various formats around the world and is committed to saving people money so they can live better. We earn the trust of our customers every day by providing a broad assortment of quality merchandise and services at every day low prices (“EDLP”) while fostering a culture that rewards and embraces mutual respect, integrity and diversity. EDLP is our pricing philosophy under which we price items at a low price every day so that our customers trust that our prices will not change under frequent promotional activity. Our fiscal year ends on January 31. During the fiscal year ended January 31, 2008, we had net sales of $374.5 billion.

Our operations comprise three business segments: Wal-Mart Stores, Sam’s Club and International.

Our Wal-Mart Stores segment is the largest segment of our business, accounting for 64.0% of our fiscal 2008 net sales and operates stores in three different formats in the United States, as well as Wal-Mart’s online retail operations, walmart.com. Our Wal-Mart Stores retail formats include:

Our Sam’s Club segment consists of membership warehouse clubs in the United States and the segment’s online retail operations, samsclub.com. Sam’s Club accounted for 11.8% of our fiscal 2008 net sales. Our focus for Sam’s Club is to provide exceptional value on brand-name merchandise at “members only” prices for both business and personal use. Our Sam’s Clubs average approximately 132,000 square feet in size.

At January 31, 2008, our International segment consisted of retail operations in 12 countries and Puerto Rico. This segment generated 24.2% of our fiscal 2008 net sales. The International segment includes numerous different formats of retail stores and restaurants, including discount stores, supercenters and Sam’s Clubs that operate outside the United States.

We maintain our principal offices at 702 S.W. 8th Street, Bentonville, Arkansas 72716, USA.

The Development of Our Company

Although Wal-Mart was incorporated in Delaware in October 1969, the businesses conducted by our founders began in 1945 when Sam M. Walton opened a franchise Ben Franklin variety store in Newport, Arkansas. In 1946, his brother, James L. Walton, opened a similar store in Versailles, Missouri. Until 1962, our founders’ business was devoted entirely to the operation of variety stores. In that year, the first Wal-Mart Discount City, which was a discount store, opened in Rogers, Arkansas. In fiscal 1984, we opened our first three Sam’s Clubs, and in fiscal 1988, we opened our first supercenter. In fiscal 1999, we opened our first Neighborhood Market.

In fiscal 1992, we began our first international initiative when we entered into a joint venture in Mexico, in which we owned a 50% interest along with Cifra S.A. de C.V. (“Cifra”). In fiscal 1998, we acquired the controlling interest in Cifra, and in February 2000, Cifra officially changed its name to Wal-Mart de Mexico, S.A. de C.V. Since fiscal 1992, our international presence has continued to expand, and at January 31, 2008, we had international operations in Argentina, Brazil, Canada, Costa Rica, El Salvador, Guatemala, Honduras, Japan, Mexico, Nicaragua, Puerto Rico, and the United Kingdom. We also operate through joint ventures in China and new planned operations through a joint venture in India in fiscal 2009.

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At January 31, 2008, we operated 971 discount stores, 2,447 supercenters, 132 Neighborhood Markets and 591 Sam’s Clubs in the United States. Internationally, at the end of fiscal year 2008, the Company operated units in Argentina (21), Brazil (313), Canada (305), Costa Rica (149), El Salvador (70), Guatemala (145), Honduras (47), Japan (394), Mexico (1,023), Nicaragua (46), Puerto Rico (54), and the United Kingdom (352). We also operated 202 stores in China through a combination of joint ventures and minority-owned subsidiaries at January 31, 2008.

The following tables provide summary information regarding the numbers, additions and square footage of our discount stores, supercenters, Neighborhood Markets and Sam’s Clubs in the United States, and the numbers and square footage of our units in our international markets for each of our fiscal years from fiscal 2004 through fiscal 2008.

WAL-MART STORES SEGMENT

STORE COUNT AND SQUARE FOOTAGE ⁽¹⁾

FISCAL YEARS ENDED JANUARY 31, 2004 THROUGH 2008

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SAM’S CLUB SEGMENT

CLUB COUNT AND SQUARE FOOTAGE

FISCAL YEARS ENDED JANUARY 31, 2004 THROUGH 2008⁽¹⁾

The number of discount stores, supercenters, Neighborhood Markets and Sam’s Clubs located in each state in the United States at January 31, 2008 is disclosed in our Annual Report to Shareholders under the caption “Fiscal 2008 End-of-Year Store Count” and is incorporated herein by reference. Portions of such Annual Report to Shareholders are included as an exhibit to this Annual Report on Form 10-K.

INTERNATIONAL SEGMENT⁽⁵⁾

UNIT COUNT AND SQUARE FOOTAGE ⁽¹⁾

FISCAL YEARS ENDED JANUARY 31, 2004 THROUGH 2008

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Our Business Segments

Our retail operations serve our customers through three segments. The Wal-Mart Stores segment includes our supercenters, discount stores and Neighborhood Markets in the United States as well as walmart.com. The Sam’s Club segment includes the warehouse membership clubs in the United States as well as samsclub.com. The International segment consists of our operations in Argentina, Brazil, Canada, China, Costa Rica, El Salvador, Guatemala, Honduras, Japan, Mexico, Nicaragua, Puerto Rico and the United Kingdom. You will find information concerning the financial results of our segments and the total and long-lived assets of each of those segments in Note 11 to the Consolidated Financial Statements and in Management’s Discussion and Analysis of Financial Condition and Results of Operations. We have incorporated by reference in this Annual Report on Form 10-K our Consolidated Financial Statements as of January 31, 2008, and for the year then ended, the Notes to the Consolidated Financial Statements, and Management’s Discussion and Analysis of Financial Condition and Results of Operations that are contained in our Annual Report to Shareholders, portions of which are included as an exhibit hereto.

Wal-Mart Stores Segment

The Wal-Mart Stores segment had net sales of $239.5 billion, $226.3 billion and $209.9 billion for the fiscal years ended January 31, 2008, 2007 and 2006, respectively. During the most recent fiscal year, no single supercenter, discount store or Neighborhood Market location accounted for as much as 1% of total Company net sales.

General. As a mass merchandiser of consumer products, the Wal-Mart Stores segment operates retail stores in all 50 states, with discount stores in 47 states, supercenters in 48 states and Neighborhood Markets in 15 states. Our discount stores range in size from 30,000 square feet to 224,000 square feet, with an average size of approximately 108,000 square feet. Supercenters range in size from 98,000 square feet to 246,000 square feet, with an average size of approximately 187,000 square feet. Neighborhood Markets range in size from 37,000 square feet to 56,000 square feet, with an average size of approximately 42,000 square feet. Customers can also purchase a broad assortment of merchandise and services online at www.walmart.com.

Merchandise. Wal-Mart discount stores and the general merchandise area of supercenters carry apparel for women, girls, men, boys and infants, domestics, fabrics and notions, stationery and books, shoes, housewares, hardware, electronics, home furnishings, small appliances, automotive accessories, horticulture and accessories, sporting goods, toys, pet food and pet accessories, cellular phones and cellular service plan contracts, cameras and supplies, health and beauty aids, pharmaceuticals, jewelry and optical and provide photo processing services. In addition, our stores offer an assortment of grocery merchandise. The grocery assortment in our supercenters consists of a full line of grocery items, including meat, produce, deli, bakery, dairy, frozen foods, floral and dry grocery. Most of our discount stores carry a limited assortment of dry grocery merchandise, while a number of our larger discount stores in some markets carry a broader assortment of grocery items, including perishable items. Neighborhood Markets are generally organized into departments such as: dry grocery, meat, produce, deli, bakery, dairy, frozen foods, floral, pharmaceuticals, photo processing, health and beauty aids, household chemicals, paper goods, general merchandise and pet supplies. The Wal-Mart Stores segment also offers financial services and products, including money orders, wire transfers, check cashing and bill payment.

Nationally advertised merchandise represents a significant portion of sales in the Wal-Mart Stores segment. We also market lines of merchandise under our private-label store brands including “Sam’s Choice,” “Great Value,” “Everstart,” “Ol’ Roy,” “Puritan,” “Equate,” “No Boundaries,” “George,” “Athletic Works,” “Durabrand,” “HomeTrends,” “Mainstays,” “Metro 7,” “Parent’s Choice,” “Ozark Trail,” “ReliOn,” “White Stag,” “Sand N Sun,” “Canopy” and “Kid Connection.” The Company also markets lines of merchandise under licensed brands, some of which include “General Electric,” “Disney,” “McDonald’s,” “Mary-Kate and Ashley,” “Better Homes & Gardens” and “Starter.”

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Sales for the Wal-Mart Stores segment by general merchandise category were as follows during the fiscal year ended:

Operations. Hours of operation for nearly all supercenters and an increasing number of discount stores and Neighborhood Markets are 24 hours each day. Hours of operation for the remaining supercenters, discount stores and Neighborhood Markets vary by location, but are generally 7:00 a.m. to 10:00 or 11:00 p.m., seven days a week. We accept a variety of payment methods including credit cards, debit cards and a private-label store credit card through a third-party provider. In addition, our pharmacy departments accept payments for prescription drugs through our customers’ health benefit plans.

Seasonal Aspects of Operations. The Wal-Mart Stores segment’s business is seasonal to a certain extent. Generally, its highest volume of sales occurs in the fourth fiscal quarter, which includes the holiday season, and the lowest volume occurs during the first fiscal quarter.

Competition. Our discount stores compete with other discount, department, drug, variety and specialty stores and supermarkets, many of which are national or regional chains. Our supercenters compete with other supercenter-type stores, hypermarts, discount stores, supermarkets, department, drug, variety and specialty stores, many of which are national or regional chains. We also compete with internet-based retailers and catalog businesses and with other retailers for new store sites.

Our ability to develop the right locations and offer value and service to our customers largely determines our competitive position within the retail industry. We employ many programs designed to meet competitive pressures within our industry. These programs include the following:

In addition to these programs, we believe our broad assortment of merchandise that provides one-stop shopping, our in-stock levels that provide confidence to our customers that we will have what they need, and our long operating hours that allow customers to shop at their convenience provide us with additional competitive advantages.

Distribution. During fiscal 2008, approximately 81% of the Wal-Mart Stores segment’s purchases of merchandise were shipped through distribution centers. The balance of merchandise purchased was shipped directly to stores from suppliers. During fiscal 2008, the Company opened two general merchandise distribution centers and two grocery distribution centers and closed two tire distribution centers. General merchandise is transported to stores primarily through our private truck fleet. However, we contract with common carriers to transport the majority of our perishable and dry grocery merchandise.

Our Wal-Mart Stores segment operations are supported by 121 distribution facilities as of January 31, 2008, located strategically throughout the continental United States. Of these 121 distribution facilities, we owned and operated 106.

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Third parties owned and operated the remaining 15 distribution facilities. In addition to servicing the Wal-Mart Stores segment, some of our Wal-Mart distribution centers also service our Sam’s Club segment for certain items.

Sam’s Club Segment

The Sam’s Club segment had net sales of $44.4 billion, $41.6 billion and $39.8 billion for the fiscal years ended January 31, 2008, 2007 and 2006, respectively. During the most recent fiscal year, no single club location accounted for as much as 1% of total Company net sales.

General. As a membership club warehouse, we operate Sam’s Clubs in 48 states. Facility sizes for Sam’s Clubs generally range between 71,000 and 190,000 square feet, with the average Sam’s Club facility being approximately 132,000 square feet. Sam’s Club also provides its members with a broad assortment of merchandise and services online at www.samsclub.com.

Merchandise. Sam’s Club offers bulk displays of brand name merchandise, including hardgoods, some softgoods, institutional-size grocery items, and selected private-label items under the “MEMBER’S MARK,” “BAKERS & CHEFS” and “SAM’S CLUB” brands. Generally, each Sam’s Club also carries software, electronics, jewelry, exercise equipment, outdoor goods, tires, office supplies and books. Most clubs have fresh departments, which include bakery, meat, produce, floral and Sam’s Cafe. Additionally, a significant number of our clubs offer photo processing, pharmaceuticals, optical departments and gasoline stations.

Sales for the Sam’s Club segment by general merchandise category were as follows during the fiscal year ended:

Operations. Operating hours for Sam’s Clubs are Monday through Friday from 10:00 a.m. to 8:30 p.m., Saturday from 9:30 a.m. to 8:30 p.m. and Sunday from 10:00 a.m. to 6:00 p.m. Additionally, all club locations offer a Gold Key program that permits business members to shop before the regular operating hours Monday through Saturday, starting at 7:00 a.m.

Sam’s Clubs are membership-only operations. A variety of payment methods are accepted at our clubs, including debit cards, some types of credit cards, and a private label and co-branded Discover credit cards through a third-party provider. In addition, our pharmacy departments accept payments for prescription drugs through our customers’ health benefit plans.

Members include both small business owners and individual consumers. Individuals who are not business owners can become Advantage members. The annual membership fee for an individual Advantage member is $40 for the primary membership card, with a spouse/household card available at no additional cost. The annual membership fee for business members is $35 for the primary membership card, with a spouse/household card available at no additional cost. In addition, business members can add up to eight business associates (add-ons) to their business account for $35 each. Businesses can also purchase Advantage memberships for their employees under a Group Membership Program. Group rates are $30 per group Advantage membership when purchasing 50 - 999 memberships and $25 per group Advantage membership when purchasing 1,000 or more memberships. Sam’s Club PLUS is a premium membership program that offers additional benefits and services. The annual fee for a Primary PLUS member (Business or Advantage) is $100. In addition, Business Plus primary members can add up to 16 business associates (add-ons) to their business membership for $35 each.

Seasonal Aspects of Operations. The Sam’s Club segment’s business is seasonal to a certain extent. Generally, its highest volume of sales occurs in the fourth fiscal quarter, which includes the holiday season, and the lowest volume occurs during the first fiscal quarter.

Competition. Sam’s Club competes with other warehouse clubs, as well as with discount retailers, retail and wholesale grocers, general merchandise wholesalers and distributors, internet-based retailers and catalog businesses. We compete with other retailers and warehouse clubs for desirable new club sites. Our ability to offer low prices and quality merchandise to meet the needs of small business members largely determines our competitive position in the warehouse club industry.

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Distribution. During fiscal 2008, approximately 65% of the Sam’s Club segment non-fuel purchases were shipped from the Sam’s Club segment’s dedicated distribution facilities and some of the Wal-Mart Stores segment’s distribution centers for certain items. Suppliers shipped the balance of the Sam’s Club purchases directly to Sam’s Club locations. Our Sam’s Club segment operations are supported by 24 distribution facilities as of January 31, 2008, located strategically throughout the continental United States. Of these 24 distribution facilities, we owned and operated 7. Third parties owned and operated the remaining 17 distribution facilities.

The principal focus of our Sam’s Club’s distribution operations is on crossdocking merchandise, while stored inventory is minimized. Crossdocking is a distribution process under which shipments are directly transferred from inbound to outbound trailers. Shipments typically spend less than 24 hours in a crossdock facility, sometimes less than an hour.

Sam’s Club uses a combination of our private truck fleet as well as common carriers to transport non-perishable merchandise from distribution centers to clubs. We contract with common carriers to transport perishable grocery merchandise from distribution centers to clubs.

International Segment

Our International segment is comprised of our wholly-owned subsidiaries operating in Argentina, Brazil, Canada, Puerto Rico and the United Kingdom, our majority-owned subsidiaries operating in Central America, Japan and Mexico, our joint ventures in India and China and our minority-owned subsidiaries in China.

The International segment’s net sales from continuing operations for the fiscal years ended January 31, 2008, 2007 and 2006, were $90.6 billion, $77.1 billion and $59.2 billion, respectively. During the most recent fiscal year, no single unit accounted for as much as 1% of total Company net sales.

General.

At January 31, 2008, our international operating formats varied by market and included: