Abstract: Objective To understand the prevalence of risk sex behaviors and HIV infection status among men who have sex with men in Chongqing in recent several years. Methods Face to face questionnaire survey was conducted among the MSM recruited by snowballing methods in the communities in Chongqing from 2010 to 2013. All the data were analyzed with SPSS 13.0 software. Results Only 6% of the MSM aged 30 years were got married, but the awareness of AIDS related knowledge was high among them. Most MSM surveyed had anal sex in the past 6 months, but the condom use rate was less than 50%. The positive rates of HIV and syphilis antibodies were high in age group 34 years. From 2010 to 2013,the HIV infection rate increased from 11.4% to 17.6% in age group 18-24 years and from 10.5% to 26.4% in age group 30-34 years. The result of logistic regression analysis showed that influencing factors of HIV infection included education level, condom usage in recent 6 months, HIV test history and syphilis infection. Conclusion Although the MSM had high awareness of AIDS related knowledge and behavior interventions had been conducted among them in Chongqing, the HIV infection rate was still high. It is urgent to conduct early antiretroviral treatment and more effective targeted behavior interventions in MSM.