Matt Shrigley led the Aztecs (23-2, 12-1 Mountain West Conference) with 15 points, while Josh Davis added 12.
Jarred Shaw and Spencer Butterfield each scored 10 points to lead Utah State (15-11, 5-9 Mountain West). The San Diego State defense forced 15 turnovers, while Skyler Spencer blocked four shots.
Preston Medlin gave Utah State a 5-4 lead with a 3-pointer, but that turned out to be the Aggies only lead of the game. The Aztecs then went on a 28-9 run to seize control of the game.
Utah State head coach Stew Morrill is still stuck on 599 career victories.
The Aggies next host Fresno State Saturday night in Logan.