She Wore a Yellow Ribbon is a 1949 Western film directed by John Ford and starring John Wayne. The film was the second of Ford's trilogy of films focusing on the US Cavalry (and the only one in color); the other two films were Fort Apache (1948) and Rio Grande (1950). With a budget of $1.6 million, the film was one of the most expensive Westerns of the time, but became a major hit for RKO and remains a popular classic today.

Known for its breathtaking views of Monument Valley located in the Navajo reservation, at the northern edge of Arizona; the cinematographer, Winton Hoch, won the 1950 Academy Award for Best Color Cinematography. Ford and Hoch based much of the film's imagery on the paintings and sculptures of Frederic Remington.

The film is named after a song common in the U.S. military, "She Wore a Yellow Ribbon", which is still used today to keep marching cadence. It is a variant of the song "All Around My Hat".