The Gators made 12-of-21 shots from 3-point range to easily remain unbeaten in Southeastern Conference action. They have a one-game lead over Mississippi in the league race.
Rosario and Boynton combined to make five of Florida's long-range shots while Michael Frazier came off the bench to add 12 points.
South Carolina trailed by 22 at the break and managed just 14 field goals for the entire game. Florida (17-2, 7-0 SEC) shot 52 percent from the field and came up with 13 steals.
Michael Carrera scored 13 points and was the only player in double figures for the Gamecocks (12-8, 2-5).