Guillaume Warmuz (born 22 May 1970) is a French football coach and former player who played as a goalkeeper.

[4] In January 2003, then a free agent Warmuz signed a short-term contract for Arsenal, as a replacement for the injured Rami Shaaban.

Warmuz featured in 17 Bundesliga matches in his first season, as the other goalkeeper Roman Weidenfeller did the same and the club finished in sixth position.

On 16 February 2008, Warmuz was appointed director of football at Gueugnon,[7] lasting eight days in office.

On 1 June 2017, Warmuz was appointed as manager of Championnat National 2 side Montceau Bourgogne.