Mabi took only 46 seconds to get on the scoresheet for his club, reigning African Champions TP Mazembe, in their 1-0 win over Malekesa on Wednesday.
Mabi was sanctioned by the game's world governing body Fifa after being found guilty of attacking a referee during a match at the 2010 Cecafa Club Cup.
The game was his first match since the end of his suspension on 11 August.
Mabi's quick return to scoring is a boost for DR Congo coach Robert Nouzaret.
The striker was named in the DR Congo squad for a friendly against Angola on 27 August and for the vital Africa Cup of Nations qualifier against Senegal in Dakar next month.