Abstract: Objective To understand the characteristics of high risk behaviors and HIV/STD infection status among men who have sex with men (MSM) in Lucheng district of Wenzhou, and provide evidence for the effective intervention and prevention/control strategy. Methods With informed consent, the anonymous questionnaire was conducted among MSM and blood samples were taken from them by well trained investigators and volunteers. Results A total of 358 MSM were interviewed and the majority were young adults with the average age of 26.966.46 years, 67.60% of them were unmarried. In the past half years, 87.71% of them had anal intercourse with males and 64.80% had more than two sexual partners (averagely 4.326.71), 39.11% had both male and female sex partners, 27.71% provide commercial sex for others. During the past half year, 56.05% of them used condom at each sex with males and 47.86% used condom at each sex with females, The positive rate of HIV, HBsAg and syphilis was 3.45%, 5.42% and 10.84% respectively. The infection rate of syphilis with HBsAg positive was 0.99% and that of syphilis with HIV positive was 1.48%. Conclusion High risk sexual behaviors are prevalent among MSM in Lucheng district, which could facilitate HIV/STD transmission, so the prevention programs and behavior intervention should be further strengthened.