The Wildcats (8-2, 5-1 Colonial Athletic Association) led by two touchdowns at the break, but Connor Frazier's 5-yard scoring pass to Tanner Vallely in the third quarter made it a one-score game, 21-14.
Robertson responded with a 1-yard touchdown run with 14:55 left to play. On Towson's ensuing drive, Frazier's pass was intercepted on second and 10 by Joe Sarnese, who returned it 48 yards for a touchdown to stretch the Wildcats' lead to 35-14.
Robertson finished with 182 yards passing and 107 on the ground.
Darius Victor led the Tigers (4-6, 2-4) with 165 yards rushing and one touchdown. Frazier threw for 111 yards, one touchdown and two interceptions.
Villanova was on a seven-game winning streak until a 10-9 loss to Richmond last Saturday.