Abstract: Objective To learn social discrimination experience,individual behavior and mental health among the men who have sex with men(MSM).Methods Respondence drived sampling(RDS) was used to recruit MSM and self-administered anonymous questionanire survey was carried out in the MSM.Results Among the 201 MSM,52(25.9%) had social discrimination experience during the pevious 6 months;40 persons(19.9%) were suspected to have health problems;34 persons(16.9%) were suspected to have mental illness;34 persons(16.9%) were suffered from undermined social prestige; 24 persons(11.9%) were out of contacts with friends.The AIDS counseling rates were higher in MSM who were suspected to have mental illness.The sexually transmitted disease were higher in MSM who were suspected to have health problems.Conclusion Social discrmi ination affects individual behavior, mentalhealth, and the tran smission of AIDS among MSM.