Ajayi opened scoring for Al Ahly in the 33rd minute in the game which was played inside the Cairo International Stadium.
Al Ahly doubled their lead in the 69th minute through Amr Al Sulaya while Mohamed Kafsha made it 3-0 on 85 minutes.
Ajayi now has four goals in 12 league appearances for Al Ahly this season.
Monday’s goal means he has scored six goals in 19 appearances in all competitions this term.
Al Ahly have now stretch their lead ahead of second placed Al Mokawloon Al Arab in the league table to 10 points, as they are now on 42 points with three games in hand.