Objective To investigate the prevalence and endoscope detection rate of proximal serrated polyps and to screen the risk factors. Methods The data of 9 010 colonoscopies performed by 22 endoscopists between September 2016 and September 2017 were reviewed. The adenoma detection rate (ADR) and proximal serrated polyp detection rate (PSDR) were calculated, and the correlation of ADR and PSDR was estimated by Pearson correlation coefficients. Multivariate logistic regression was used to analyze PSDR among endoscopists. Results For all subjects, the mean ADR was 30.07% (ranged from 20.00% to 40.78%) and mean PSDR was 4.70% (ranged from 1.52% to 9.28%). PSDR of males was 1.38 times of that of females (OR=1.38, 95%CI: 1.13-1.69, P＜0.01). For 3 560 cases (39.51%) of 50 years and older subjects, the mean ADR was 45.01% (28.99%-57.78%) and mean PSDR was 6.08% (2.07%-10.56%). PSDR was moderately correlated with ADR (r=0.48, P=0.02). PSDR of males was 1.36 times of that of females (OR=1.36, 95%CI: 1.04-1.80, P=0.03). Endoscopist was a significant risk factor for detection of proximal serrated polyps (P<0.01). Compared to endoscopist with the highest detection rate, odds ratio of other endoscopists ranged from 0.16 (95%CI: 0.06-0.40) to 0.83 (95%CI: 0.53-1.32). Conclusion Proximal serrated polyp has a high detection rate by endoscope in males, who are over 50 years old. The PSDR is highly variable and dependent on endoscopists. It is possible that a certain proportion of proximal serrated polyps are missed during colonoscopy.