2003 Big West Conference men's basketball tournament

The 2003 Big West Conference men's basketball tournament was held March 13–15 at Anaheim Convention Center in Anaheim, California.

Utah State defeated in the championship game, 57–54, to obtain the fifth Big West Conference men's basketball tournament championship in school history.

The Aggies participated in the 2003 NCAA Division I men's basketball tournament after earning the conference's automatic bid.

Format
Eight of the ten teams in the conference participated, with and  not qualifying. Teams were seeded based on regular season conference records.