The win ensured the soldiers moved to fourth position in the league table. The sugar millers came into the match aiming at getting their first win in seven league outings, but were undone by Daniel Waweru's first half penalty from the penalty spot.
The referee had awarded the hosts that penalty after Yusuf Juma handled the ball in the danger zone.
The hosts started the match brightly, with Samuel Onyango coordinating well upfront with Daniel Waweru and Enosh Ochieng, who had been selected ahead of Stephen Waruru.
Chemelil will regret the chances missed by Moses Arita and Neto Collins, as the team did everything to get something before the break, and later into the game. The result puts the sugarcane farmers in the 12th position with 24 points.
Ulinzi Stars XI: James Saruni, Oliver Ruto, Geofrey Kokoyo, Omar Mbongi, Boniface Onyango, Cliff Kasuti, Churchil Muloma, Enosh Ochieng, Daniel Waweru and Samwel Onyango,
Subs: Jacktone Ochieng, Michael Otieno, Abdalla Hamisi, Onwonga Justine and Stephen Waruru.