Abstract: Objective To understand AIDS related knowledge awareness, high-risk behavior, preventive services and previous HIV detection received in men who have sex with men (MSM) in Huzhou, and provide scientific evidence for the development of AIDS prevention and control measures. Methods Questionnaire survey was conducted among MSM through internet. Results Totally 410 valid questionnaires were collected from MSM. The awareness rate of AIDS related knowledge was 67.1%, the differences on awareness rate among MSM in different age group, in different population, with different education level, with different dwelling (duration), with different economic income level and with different self identification of sexual orientation were statistical significant (P0.01). The MSM having 2 or more sex partners in the past 6 months accounted for 34.4%. The MSM having more than 3 homosexual activities in the past month accounted for 44.4%, the MSM using condom in the latest sex accounted for 39.2% and the MSM using condom in each sex during the past six months accounted for 19.9%. Up to 85.6% of MSM believed condom using would prevent homosexual transmission of HIV and 77.1% agreed to use condom in the future. The main influence factors on condom using included sexual pleasure reduction (41.2%), no condom available (26.3%) and unwilling of sex partners (21.5%). Totally 46.1% of MSM had received AIDS prevention services (health education, condom delivery and counseling). Conclusion The awareness rate of AIDS related knowledge was low, but the prevalence of unprotected sex and multi partner sex were high among the MSM in Huzhou. It is necessary to strengthen the health education and intervention among MSM to effectively control the sexual transmission of HIV.