In his ninth season, Dement has had just one losing campaign but failed to lead the school to an NCAA Tournament appearance. The Mustangs are 10-15 overall and 4-11 in the Western Athletic Conference this season.
The final straw for Dement was Thursday's embarrassing 89-50 home loss to Boise State. SMU has seven double-digit losses this season, including a 35-point defeat on national television to Oklahoma State and an 80-40 rout against Rice.
The Mustangs started the season with a 6-3 record, including wins over tournament hopefuls Texas Tech and Purdue. But they have lost 12 of 16 since that impressive beginning.
Dement, who has one year remaining on his contract and had asked for an extension prior to the season, has posted a 138-120 record at the school.