1998 Big West Conference men's basketball tournament

The 1998 Big West Conference men's basketball tournament was held March 6–8 at Lawlor Events Center in Reno, Nevada.

Utah State defeated in the championship game, 78–63, to obtain the second Big West Conference Men's Basketball Tournament championship in school history. This was the first time Utah State won the title since 1988.

The Aggies participated in the 1998 NCAA Division I men's basketball tournament after earning the conference's automatic bid.

Format
Eight of the 12 teams in the conference participated, with, , , and not qualifying. The top eight teams were seeded based on regular season conference records.