Guard Solomon Bozeman came off the bench to score 17, going 5-for-6 shooting, including four 3-pointers and was a perfect 3-of-3 from the free throw line.
The Bulls (1-3) had a 52-25 halftime lead on the Owls and opened the first 10 minutes on a 30-13 run. FAU was down by at least 20 points throughout the second half.
Guard Jesus Verdejo also scored 13, while Gransberry, who went 8-of-13 shooting, added a game-high 9 rebounds. Guard Paul Graham III had a game-high 23 points, shooting 6-of-12 inside the point, while forward Carlos Monroe contributed 15 on 5-of-11 shooting.
The Owls (1-3) shot just 38 percent in the paint in the first half and allowed USF to score 34 points off the bench.
Saturday's win marks the first for Bull's first-year head coach Stan Heath and the first time South Florida scored 100 points against an opponent since Jan. 5, 2002, when the Bulls had 117 against TCU.