The United States Air Force Academy (USAFA) is a United States service academy in Air Force Academy, Colorado, immediately north of Colorado Springs. It educates cadets for service in the officer corps of the United States Air Force and United States Space Force. It is the youngest of the five service academies, having graduated its first class 66 years ago in 1959, but is the third in seniority. Graduates of the academy's four-year program receive a Bachelor of Science degree and are commissioned as second lieutenants in the U.S. Air Force or U.S. Space Force. The academy is also one of the largest tourist attractions in Colorado, attracting approximately a million visitors each year.

Admission is competitive, with nominations divided equally among Congressional districts. Recent incoming classes have had about 1,200 cadets; since 2012, around 20% of each incoming class does not graduate. During their tenure at the academy, cadets receive tuition, room and board, and a monthly stipend all paid for by the Air Force. On the first day of a cadet's second class year, cadets commit to serving a number of years as a commissioned officer in the Air Force or Space Force. Non-graduates after that point are expected to fulfill their obligations in enlisted service or pay back full tuition. The commitment is normally five years of active duty and three years in the reserves, although it has varied depending on the graduate's Air Force Specialty Code or Space Force Specialty Code.

Air power advocates had pushed for a separate Air Force Academy to complement the U.S. Military Academy (founded in 1802) and Naval Academy (1845) almost since the dawn of military aviation. In 1918, Lieutenant Colonel A.J. Hanlon wrote, "As the Military and Naval Academies are the backbone of the Army and Navy, so must the Aeronautical Academy be the backbone of the Air Service. No service can flourish without some such institution to inculcate into its embryonic officers love of country, proper conception of duty, and highest regard for honor." Other officials expressed similar sentiments. In 1919, Representative Charles F. Curry introduced legislation providing for an Academy, but concerns about cost, curriculum and location led to its demise. In 1925, air power pioneer General Billy Mitchell testified on Capitol Hill that it was necessary "to have an air academy to form a basis for the permanent backbone of your air service and to attend to the ... organizational part of it, very much the same way that West Point does for the Army, or that Annapolis does for the Navy." Mitchell's arguments did not gain traction with legislators, and it was not until the late 1940s that the concept of the United States Air Force Academy began to take shape.

Support for an air academy got a boost with the National Security Act of 1947, which provided for the establishment of a separate air force within the United States military. As an initial measure, Secretary of the Air Force W. Stuart Symington negotiated an agreement where up to a quarter of West Point and Annapolis graduates could volunteer to receive their commissions in the newly established Air Force. This was only intended to be a short-term fix, however, and disagreements between the services quickly led to the establishment of the Service Academy Board by Secretary of Defense James Forrestal. In January 1950, the Service Academy Board, headed by Dwight D. Eisenhower, then president of Columbia University, concluded that the needs of the Air Force could not be met by the two existing U.S. service academies and that an air force academy should be established.

Following the recommendation of the board, Congress passed legislation in 1954 to begin the construction of the Air Force Academy, and President Eisenhower signed it into law on 1 April of that year. The legislation established an advisory commission to determine the site of the new school. Among the panel members were Charles Lindbergh, General Carl Spaatz, and Lieutenant General Hubert R. Harmon, who later became the academy's first superintendent. The original 582 sites considered were winnowed to three: Alton, Illinois (by purchasing Principia College); Lake Geneva, Wisconsin (near Big Foot Beach State Park); and the ultimate site at Colorado Springs, Colorado. The Secretary of the Air Force, Harold E. Talbott, announced the winning site on 24 June 1954. Meanwhile, Air Training Command (ATC) began developing a detailed curriculum for the academy program.

From 1954 to 1956, the new Colorado Land Acquisition Commission purchased parcels of land that would host the new academy. The first parcel purchased was also the largest; it was the 4,630-acre (1,870 ha) Cathedral Rock Ranch, owned by Lawrence B. Lehman of the Lehman investment family. The purchase price was $300,000, or about $65 per 1-acre (4,000 m²). 140 parcels were eventually purchased to create what is now a nearly-18,500-acre (7,500 ha) government property.

Early Air Force Academy leaders could look at West Point and Annapolis in designing an appropriate curriculum, faculty, and campus. The academy's permanent site had not been completed when the first class entered, so the 306 cadets from the Class of 1959 were sworn in at a temporary site at Lowry Air Force Base in Denver on 11 July 1955. While at Lowry, they were housed in renovated World War II barracks. There were no upper-class cadets to train the new cadets, so the Air Force appointed a cadre of "Air Training Officers" (ATOs) to conduct training. The ATOs were junior officers, many of whom were graduates of West Point, Annapolis, VMI, and The Citadel. They acted as surrogate upper-class cadets until the upper classes could be populated over the next several years. The academy's dedication ceremony took place on that first day and was broadcast live on national television, with Walter Cronkite covering the event. Arnold W. Braswell was commander of the original four cadet squadrons at the academy 1955 to 1958.

In developing a distinctive uniform for cadets, the Air Force turned to Hollywood. Film director Cecil B. DeMille designed the cadet parade uniform still in use.