Arkansas (8-3, 4-3) can win the SEC West with a home victory next week against 20th-ranked Louisiana State.
The Razorbacks based their offensive attack around Howard, who recorded his first career 100-yard game on 25 carries.
Mark Pierce scored on his only carry of the game and also had a touchdown reception as Arkansas built a 26-6 lead entering the fourth quarter.
Arkansas quarterback Matt Jones attempted only 14 passes, but completed eight and threw a pair of touchdowns.
The Bulldogs (3-8, 0-7) tried to rally, closing to within 26-19 with 3:20 remaining. But Mississippi State's hopes ended when it turned the ball over on downs at the Arkansas 19 with 52 seconds left.
Mississippi State has dropped seven straight conference games for the first time since 1995. The Bulldogs need to beat Mississippi on Thanksgiving to avoid their first winless SEC season in 1985.
Justin Griffith ran 13 times for 72 yards for the Bulldogs, while quarterback Kyle York tossed a pair of touchdown passes in relief of Kevin Fant.