A 2-2 draw in the second leg of the final in Garoua ensured success for the Cairo team after their 2-0 victory in the first leg two weeks ago.
Al Ahli, competing in the final for a fourth successive year, held off a second half comeback from their hosts to book a place at next month’s World Club Cup in Japan.
The boisterous home crowd were given hope of a comeback when Karim Abdoul equalised with a shot from the edge of the penalty area on the stroke of half-time.
Coton Sport, needing three more goals to turn around the aggregate scoreline, took the game to their visitors after the break.
They managed one more goal just past the hour mark when Baba Ousmaila headed home from a free kick.
Despite running Al Ahli ragged, Coton Sport’s strikers still spurned several good chances with Ousmaila and Daouda too hasty in executing their chances.
Al Ahli kept up their unbeaten run in the latter stages of this year’s competition when Mohamed Barakat was pushed in Coton Sport’s penalty area in second half added time and captain Shady Mohamed converted from the spot.
Al Ahli had previously held the record of five Champions League wins jointly with compatriots Zamalek.
Coton Sport were competing in the final for the first time, hoping to become the first side from Cameroon to win Africa’s top club prize in 28 years.