Little Rock trailed 11-0 to start the game, but used runs of 14-3 and 13-3 to build a 34-30 lead by halftime.
The Trojans limited South Alabama to 9-of-30 shooting in the second half - including a nine-minute field-goal drought. Shaq Calhoun's dunk with 12:55 left pulled South Alabama to 44-41, but the Jaguars' next basket didn't come until John Brown's 3-pointer with 3:54 remaining.
Little Rock went on a 17-6 run, with scoring from six different players, during South Alabama's drought for a 61-47 lead.
Jalen Jackson added 11 points for Arkansas Little Rock (11-1).
Brown scored 15 points for South Alabama (5-7). Calhoun added 14 and Georgi Boyanov recorded his third straight double-double with 12 points and 12 rebounds.