The goals were scored by Dario Monteiro and Daine Klate.
The victory sees Matsatsantsa surge six points clear at the head of the Absa Premiership table, though closest chasers Mamelodi Sundowns do have two games in hand.
There were few highlights in the first 45 minutes, with both sides finding goal scoring opportunities hard to come by.
Stars were the first to threaten, with left winger Matome Madimabe driving a powerful shot just wide of Emille Baron’s right hand post in the 28th minute.
But a typically clinical attacking move from SuperSport saw them take the lead on 37 minutes.
A swift passing movement put Daine Klate free down the left and the winger played a good pass across the penalty area to Dario Monteiro; the Mozambican took one touch and then beat Kennedy Mweene at his near post with a powerful low shot.
Both Gavin Hunt and his counterpart Gordon Igesund felt that their sides could improve in the second stanza and thus made a substitution each at the resumption: Liberian Anthony Laffor replaced Tebogo Langerman for United, while Ea Lla Koto’s Sifiso Thomo came on for Elder Richartz.
Laffor should have helped to put his side two goals up in the 54th minute when he broke free down the right flank, but he dallied on the ball and allowed Martin Carelse to come across and make a good interception.
On 66 minutes Stars should have drawn level. Madimabe provided a perfect cross from the left for Thomo but the substitute miscued his shot horribly wide from just three metres out.
Three minutes later Stars were made to pay for the miss as United doubled their lead. A great diagonal ball from Ricardo Katza, who had just come on, set Hlompho Kekana free down the right; the wingback went for goal himself and forced a good save from Mweene, but Klate was on hand at the far post to tuck home the loose ball.
Laffor should have made it 3-0 on 77 minutes but he shot over the bar from ten yards out after great play down the right by-line by Jabu Maluleke.
United were fortunate not to concede a penalty a short while later when Paulus Masehe’s goal-bound shot was handled by a SuperSport defender inside the 18-yard box. Referee Abdul Ebrahim failed to spot the offence.
Klate almost bagged a third for the hosts in the final minute of regulation time but his fine effort rebounded off the woodwork.