كتب : Ahmad Saied
They advance on a one-goal aggregate triumph as they held Pirates to a goalless away draw two weeks ago.
Tarek Ziadi notched the winner in the 41st minute when he converted Joetex Frimpong's cross into the back of the net.
Ziadi missed the first leg, which was Sfaxien's only game in the tournament without a goal, due to suspension.
Sfaxien will know their opponents in the final on Sunday when title holders Ahli take on Ivory Coast champions ASEC Mimosas.
Ahli play the game as favorites as they travel to Abidjan enjoying a two-goal lead from the first leg.