War Eagle is a battle cry, yell, or motto of Auburn University and supporters of Auburn University sports teams. War Eagle is a greeting or salutation among the Auburn Family (e.g., students, alumni, fans). It is also the title of the university's fight song and the name of the university's golden eagle.

The widespread use of "War Eagle" by Auburn devotees has often led to outside confusion as to Auburn's official mascot. However, the official mascot of Auburn University is Aubie the Tiger, and all Auburn athletic teams, men's and women's, are nicknamed the Tigers. Auburn has never referred to any of its athletic teams as the "Eagles" or "War Eagles." The university's official response to the confusion between the Tigers mascot and the War Eagle battle cry is, "We are the Tigers who say 'War Eagle.'"

Since 1930, and continuously since 1960, Auburn has kept a live golden eagle on campus. Since 2001 Auburn has presented an untethered eagle to fly over Jordan-Hare stadium prior to the start of football games. War Eagle VIII, a golden eagle named Aurea, along with Independence, a bald eagle, perform the War Eagle Flight before all Auburn home games at Jordan–Hare Stadium.

As early as 1916, the Columbus, Georgia Daily Enquirer mentioned "War Eagle" as an Auburn battle cry. In the 1846 edition of Francis Parkman's study of the Plains Indians The Oregon Trail, the term "War Eagle" is used to describe the feathers in the headdress of various Dakota tribe members. In the 19th and early 20th centuries, "War Eagle" appeared from time to time in the United States as an evocative nickname for people and things such as Native Americans (including professional wrestlers); race horses; a U.S. civil war mascot; and, in one case, a coal mine interest.

There are several stories about the origin of the battle cry. One of these is a mythical story published in 1959 in the Auburn Plainsman, conceived by its then editorial page editor, Jim Phillips. This myth is detailed below under War Eagle I. Another mythical story is told about an Auburn student who returns to the University after the war with an eagle who was wounded on the battlefield with him but he nursed back to health. The eagle soared above the field in 1892 as Auburn scored the winning touchdown as the crowd chanted "War Eagle!" Just then, the eagle fell to the ground dead from age but was to live on as the Auburn football battle cry for generations to come.

A 1914 football game against the Carlisle Indians provides another myth. According to this story, there was a lineman/tackle named Bald Eagle on the Indians' team. Attempting to exhaust that player, Auburn's team began running multiple plays directly at his position. Without even huddling, the Auburn quarterback Lucy Hairston would yell "Bald Eagle," letting the rest of the team know that the play would be run at the tackle. Spectators, however, thought the quarterback was saying "War Eagle," and began to chant that.

Another legend claims that "War Eagle" was the name given to the large golden eagle by the Plains Indians because the eagle furnished feathers for use in their war bonnets.

According to a 1998 article in the Auburn Plainsman, the most likely origin of the "War Eagle" cry grew from a 1913 pep rally at Langdon Hall, where students had gathered the day before the annual football game against the University of Georgia. Cheerleader Gus Graydon told the crowd, "If we are going to win this game, we'll have to get out there and fight, because this means war." During the frenzy, another student, E. T. Enslen, dressed in his military uniform, noticed something had dropped from his hat. Bending down, he saw it was the metal emblem of an eagle that had come loose during his wild cheering. Someone asked him what he had found, and Enslen loudly replied, "It's a War Eagle!" The new cry was used by students at the game the following day.