The 2004 Prix de l'Arc de Triomphe was a horse race held at Longchamp on Sunday 3 October 2004.

[1] It was the 83rd running of the Prix de l'Arc de Triomphe.

The winner was Bago, a three-year-old colt trained in France by Jonathan Pease.

The winning jockey was Thierry Gillet.

[2] Further details of the winner, Bago.