Deising made field goals of 36 and 32 yards in the first quarter to give Jackson State (3-5, 3-3 Southwestern Athletic Conference) a 6-0 lead.
Mississippi Valley State's Farrean Toney returned an interception 32 yards for a score, but the PAT-attempt by Ruben Piraquive was blocked and the teams went into halftime tied at 6.
Piraquive kicked a 27-yard field goal and Slade Jarman scored on a 2-yard run to give MVSU (0-9, 0-7) a 16-6 lead with 2:59 left in the third quarter.
Jackson State, which limited the Delta Devils to 131 total yards, scored the final 17 points to pull away.
Mississippi Valley State has lost 13 in a row.