On fourth-and-11, Robinson rolled to the right before throwing to Bell who caught the deflected pass in the end zone for a 17-6 lead early in the fourth quarter.
Jordan Williams scored on an 11-yard run with 3:14 remaining but a conversion pass failed
Khalid Thomas rushed for 139 yards on 29 carries for the Hornets (5-4, 5-3 Southwestern Athletic), who won their third straight.
Alabama State's Ellis Richardson ran 2 yards in the first quarter and David Albert added a field goal for a 10-0 halftime lead.
Kwame Bowens blocked a punt and returned it 13 yards for Jackson State (3-6, 3-4) in the third quarter.
Alabama State lost three fumbles and Jackson State four on a field made soggy by a game-long rain.