Objective: To investigate the status of regular HIV testing and post exposure prophylaxis (PEP) behaviors among men who have sex with men (MSM) in Lishui City, Zhejiang Province, so as to provide the reference for developing targeted intervention strategies. Methods: A total of 389 MSM were selected from Lishui City by convenient sampling method from April to August 2022, and demographic information, sexual behaviors, HIV testing and PEP behaviors were collected through questionnaire surveys. MSM were clustered using two step clustering analysis, and regular HIV testing and PEP behaviors among different groups of MSM were compared. Factors affecting regular HIV testing and PEP behaviors were evaluated using a multivariable logistic regression model. Results: The MSM surveyed had a median age of 31.00 (interquartile range, 16.00) years. There were 146 MSM undergoing regular HIV testing, accounting for 37.53%, and 47 MSM receiving PEP, accounting for 12.08%. MSM were divided into two groups. There were 28.05% of MSM with regular HIV testing in group 1, which was lower than the 44.44% in group 2; and 22.56% receiving PEP, which was higher than the 4.44% in group 2 (both P<0.05). Multivariable logistic regression analysis identified age (OR=1.030, 95%CI: 1.011-1.050), sexual roles (both receptive and insertive, OR=2.999, 95%CI: 1.732-5.194) and homosexual behaviors in the past 6 months (use condoms every time, OR=4.567, 95%CI: 2.593-8.044) as factors affecting regular HIV testing among MSM; age (OR=0.970, 95%CI: 0.942-0.999), sexual orientation (OR=0.292, 95%CI: 0.139-0.612) and homosexual behaviors in the past 6 months (not use condoms, OR=0.135, 95%CI: 0.040-0.460; use condoms every time, OR=0.076, 95%CI: 0.018-0.326) as factors affecting PEP behaviors among MSM. Conclusion MSM with different characteristics of sexual behaviors have different preferences for HIV regular testing and PEP, with homosexual behaviors in the past 6 months, sexual roles and sexual orientation being the main influencing factors.