The Terrapins had given up 200 yards on the ground in the first two quarters and faced a 17-6 halftime deficit.
Also in the second half, quarterback Chris Turner threw a third-quarter touchdown pass to Torrey Smith and Da'Rel Scott scored on a 1-yard fourth-quarter run.
Turner completed 16 of 30 passes for 174 yards, while speedy wide receiver Darius Heyward Bey set up a touchdown with a 76-yard run on a reverse in the third quarter, and six different receivers caught passes for the Terrapins (4-1, 1-0 ACC).
It was their second straight victory at Clemson's Death Valley.
Clemson running backs James Davis and C.J. Spiller combined for 230 rushing yards and both scored touchdowns.
Quarterback Cullen Harper went 15-of-22 passing for 151 yards with one interception for the Tigers (3-2, 1-1).