In an internal memo posted by Chinese media and confirmed as accurate by an Honor spokesperson, Zhao said he was stepping down due to health reasons and planned to rest, recover and spend more time with his family.
Zhao called the decision to leave Honor "the most difficult decision" he has ever made.
The move comes as Honor looks to pull off an IPO which it first announced in 2023.
Honor was spun off from Chinese telecommunications giant Huawei in 2020 in a bid to avoid U.S. sanctions that were crippling Huawei's smartphone business.