كتب : وكالات
The five-time champions won 1-0 in Niamey, courtesy of a second-half strike by Egypt international Hazem Emam.
The victory sends Zamalek through to the second round, where they meet Angola's Kabuscorp.
Kabuscorp, who won the Angolan league for the first time last year, brushed aside Seychelles Cote d'Or 7-2.
Holders Ahli, Egypt's other representatives, will meet Tanzania's Young Africans.
VIDEOS
Chance missed by Douanes after a clear foul on Zamalek defender Mahmoud Fathallah.
Abdul-Wahed Al-Sayed saves Zamalek with a fine save before half time.
Emam scores Zamalek goal with a counter attack move that ended with a good assist from Ahmed Gaafar.