The 2015–16 Saint Mary's Gaels men's basketball team represented Saint Mary's College of California during the 2015–16 NCAA Division I men's basketball season.

This was head coach Randy Bennett's fifteenth season at Saint Mary's.

The Gaels competed in the West Coast Conference and played their home games at the McKeon Pavilion.

They defeated Loyola Marymount and Pepperdine to advance to the championship game of the WCC tournament where they lost to Gonzaga.

As a #2 seed, they defeated New Mexico State and Georgia to advance to the quarterfinals where they lost to Valparaiso.