The study investigated the effect of endoscopist characteristics and artificial intelligence (AI) on adenoma detection during colonoscopy in a sample of 17,604 patients in China between January 2021 and August 2022. The results showed that female endoscopists achieved a higher adenoma detection rate (ADR) compared to male endoscopists, and this difference was statistically significant (AOR 1.273). Female endoscopists demonstrated better performance especially in the detection of small adenomas and lesions located in the proximal colon. AI assistance improved adenoma detection in male endoscopists (AOR 1.166), bringing their performance closer to that of women without AI support, but AI had no significant effect on the performance of female endoscopists. After the introduction of AI, the ADR in male endoscopists increased to 28.77%, reducing the gender gap. The study concluded that endoscopist characteristics, especially gender and experience, along with AI assistance, have a significant impact on the quality of adenoma detection during colonoscopy.