The veteran midfielder broke the deadlock on 23 minutes at Al Salam Stadium and Islam Mohareb added a second goal for the ‘Red Devils’ three minutes before half-time.
Victory stretched to seven matches the unbeaten Champions League run of record eight-time champions Ahly since French coach Patrice Carteron took over this year.
It was the first loss in seven African matches for twice winners Setif, who knocked out defending champions Wydad Casablanca of Morocco in the quarter-finals.
Ahly could have won more convincingly as Moroccan Walid Azaro and Ahmed Hamoudi were foiled by the woodwork and the former scored only to be judged offside.
Superstitious Ahly supporters with long memories will be a little nervous, though, ahead of the return match in Algeria on October 23.
Ahly also defeated Setif 2-0 at home the last time they met in the semi-finals of the competition 30 years ago, but the Egyptians lost the tie after a penalty shootout.
Earlier, Primeiro Agosto of Angola edged Esperance of Tunisia 1-0 in a foul-littered first leg in Luanda settled by an 80th-minute goal from Luvumbo ‘Bua’ Pedro.
The substitute pounced on a loose ball just outside the box and his shot went into the net off the hands of goalkeeper Rami Jeridi.
Esperance came close to levelling in stoppage time when a Haythem Jouini glancing header was just off target.
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