Abstract: Objective To examine HIV prevalence and risk of HIV secondary transmission among men who have sex with men in Liaoning province. Methods A face-to-face questionnaire interview was conducted among men who have sex with men(MSM)recruited wtih snow ball sampling method in 6 main cities of Liaoning province from April to June,2008. Blood specimens were collected for HIV and syphilis testing. Results A total of 2 074 MSM were recruited for the survey. The prevalence of HIV and syphilis was 4.8%(100/2 074)and 8.9%(184/2 074),respectively.Among the MSM,the average number of homosexual partners was 5.8 and the condom using rate during anal sex with regular male sexual partner, commercial sexual partner,and male casual sexual partner were 43.3%(899/2 074),65.0%(286/440),and 68.5% (1 421/2 074),respectively.The proportion of MSM who had female sexual partner was 51.6%(1071/2 074),in which 50.3%(294/585)used condom during intercourse with the last female sexual partner.Multivariate logistic analyses indicated that syphilis infection(odds ratioOR=4.6,95%confidence intervalCI:2.3-9.2),inconsistent condom use during receptive anal sex(OR=2.8,95%CI:1.4-5.5),the munber of homosexual partners≥10(OR=2.0,95%CI:1.0-3.8), and education(OR=1.8,95%CI:1.0-3.3)were independent risk factors for HIV infection. Conclusion The prevalence of HIV and syphilis among the MSM in Liaoning province has reached a high level.High proportion of MSM had heterosexual partners and low condom using rate during their heterosexual intercourse.Effective behavioral intervention program should be carried out among the MSM to decrease the risk of HIV secondary transmission to general population by unprotected sexual behavior.