"Moesha" star Marcus Paulk just dodged jail time for socking his girlfriend in the stomach -- courtesy of a plea deal.

TMZ broke the story ... Paulk was arrested last August when he and his GF exchanged blows in a nasty fight that ended with him allegedly kicking and punching her in the gut.

According to court docs, Marcus plead no contest to one count of battery, and got 4 other charges dropped. As part of the deal, he must enroll in a year-long domestic violence treatment program.

The deal also includes a protective order for Marcus to stay 100 yards away from his now EX lady friend.