The 2004–05 Saint Mary's Gaels men's basketball team represented Saint Mary's College of California in the 2004–05 college basketball season, coached by Randy Bennett for the 4th year.

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

They finished conference play with a record of 11–3 to place second.

They reached the semifinal round of the 2005 West Coast Conference men's basketball tournament, but received an at-large bid to the 2005 NCAA Division I men's basketball tournament where they entered as the No.

7 seed Southern Illinois in the opening round[2] to end their season 25–9.