Leading 58-56 with just over seven minutes left, the Gamecocks (1-1) used a 14-2 run to secure their first win of the season after an opening loss to Central Michigan on Friday.
Townser made three 3-pointers and was one of four Jacksonville State players to score at least 14 points. Jared Hamilton had 13 rebounds to go along with his 14 points.
Tyler Edwards and Jaylon McMillan both had 11 points for Fort Valley State (1-2), which shot 52 percent from the field and got 44 points from its bench. The Wildcats only attempted 17 free throws compared to the Gamecocks' 38, and they trailed in second-chance points 17 to 5.
Jacksonville State led 38-37 at the break.