Ryan Spiteri put the Spartans ahead but a brace by Alan Tabone gave Zebbug the three points.
In another match, St. Andrews were held in a 2-2 draw by Zurrieq.
Trayo Grozev put the Saints ahead on 36 minutes but Glenn Bonello equalised just before half-time. Emiliano Lattes restored the lead on 62 minutes but Bonello notched the equaliser in added time.
Pietà lead the way with 18 points, followed by Zebbug on 14, Melita and Lija 13, St. Andrews 12, Zejtun and Birzebbuga 10, St. George’s and Gzira 9, Zurrieq 8, Gudja 7, Msida 4 and Hamrun -3.