To examine the correlates for syphilis and the prevalence for HIV, hepatitis B, hepatitis C among men-who-have-sex-with-men (MSM) in Beijing, China. A total of 541 MSM was recruited using peer-referral, community outreach, and Internet. Questionnaire-based interviews provided information including, demographics, sexual and other risk behaviors. HIV prevalence was 4.8%, syphilis 19.8%, HCV 0.4% and HBsAg 6.5%. The median number of lifetime male sex partners was ten. In the past 3 months, 20.7% drank alcohol > or =1 times per week. In the past month, 21.3 and 14.6% had unprotected anal intercourse with regular and casual male sex partners, respectively. Syphilis infection was associated with less education, alcohol use, finding male sex partners through bathhouses/public washrooms/parks, and diagnoses of sexual transmitted diseases (STDs). Syphilis is now epidemic among Beijing's MSM. Prevention efforts are urgent as HIV prevalence is already near 5%. Education, condom promotion, STD control, and alcohol-related intervention are needed urgently.