Abstract: Objective To evaluate the impact of sexual behaviors among HIV-infected men who have sex with men (MSM) after one year of antiretroviral treatment. Methods A face-to-face questionnaire interview was administrated to collect the information about high-risk behaviors of survey objects before and after one year antiretroviral treatment. Differences in sexual behavior were assessed by using the McNemar χ² text. Qualitative research with individual interviews was conducted to explore the factors of continuing high-risk behaviors after antiretroviral treatment. Results A total of 132 cases were investigated, with a high rate of condom use in the anal intercourse among respondents and the regular partners, 91.4% and 87.1% before and after treatment, with no statistical difference (χ²=1.500, P=0.682), anal intercourse with casual partners the condom use rate was 22.2% and 28.3% respectively before and after treatment, and the difference was statistically significant (χ²=11.257, P=0.010). Treatment success rate of patients with unprotected anal intercourse was lower than no unprotected anal intercourse behavior, 82.4% and 95.7% respectively, and the difference was statistically significant (χ²=4.601, P=0.032). Conclusions Among MSMs HIV-infected patients/AIDS patients after antiviral treatment a year later, there were still some of the subjects had unprotected anal intercourse with accidental sexual partners, increased the risk of HIV-resistant strains of transmission and sexually transmitted diseases risk, promotion of education and behavioral intervention for the target population should be further strengthened.