Elvis Nandwa netted his eighth goal of the season with Enosh Ochieng finding the target for the second time this campaign to help Dunstan Nyaudo pick three crucial points on the road.
Ochieng scored Ulinzi’s second goal with six minutes left on the clock to add to Nandwa’s opener.
Sydney Lokale came off the bench to make the difference with a second-half goal after he replaced George Abeg.
Lokale tapped in Bolton Omwenga's cross from inside the box to hand William Muluya the first three points.
The win saw Sharks move two places up the league standings with 37 points from 28 matches played so far.