Benoun has made just two substitute appearances in over eight months after being sidelined for long due to a heart condition that followed a COVID-19 infection.
He contracted the highly-contagious virus while on international duty, just before Morocco headed to Cameroon to take part in the January-February African Cup of Nations.
"The player informed football director Sayed Abdel-Hafiz that he would like to move to Qatar for personal reasons," Ahly said in a statement on their official website.
"Coach Ricardo Soares said he can't force the player to carry on if he has adaptation problems … and that he agrees to let him join the Qatari club.
"Benoun flew to Qatar to undergo a medical before completing the deal," the Cairo giants added, without revealing the length of the contract or the transfer fee.
The 28-year-old has been one of Ahly's key players since joining in November 2020. A towering center back, he proved the most reliable among the team's central defenders.
He helped the Red Devils to an African Champions League crown, an Egypt Cup title, an African Super Cup triumph and a third-place finish at the 2020 FIFA Club World Cup.
Benoun's last appearance came in a 4-1 Egyptian Premier League win over Eastern Company on 15 June.
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