The 2019–20 Saint Mary's Gaels men's basketball team represented Saint Mary's College of California during the 2019–20 NCAA Division I men's basketball season.

The team was led by head coach Randy Bennett in his 19th season at Saint Mary's.

The Gaels played their home games at the University Credit Union Pavilion in Moraga, California as members of the West Coast Conference.

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

Despite being a virtual lock to receive an at-large bid to NCAA tournament, all postseason play was cancelled amid the COVID-19 pandemic.