ObjectiveTo investigate online dating status and human immunodeficiency virus  (HIV) infection among men who have sex with men  (MSM) in Chongqing， and provide basis for effective intervention in HIV infection among MSM.Methods206 MSM in Chongqing were performed structured interview and questionnaire survey，MSM who didn’t conduct HIV testing within half a year were performed laboratory screening， sociological population characteristics and influencing factors of HIV in MSM were analyzed. ResultsThe average age of 206 MSM was (22.08±1.81) years old, 137 (66.50%) received college education and above, HIV infection rate was 21.36%（44/206）. HIV infection rate in MSM who had no fixed partners was higher than those who had  fixed partners; the more sexual partners they had, the greater the risk of HIV infection they got;  HIV infection rate in MSM who had sex with unfamiliar persons or strangers was higher than those who had sex with familiar partners; the higher rate of condom use in sexual behavior, the lower rate of HIV infection was, there were significant differences among the groups(all P＜0.05). Condom use among MSM with different educational levels was significantly different(all P<0.05). ConclusionHIV infection rate in MSM is high in this city, it is necessary to strengthen education about health, network partner, and  behavioral intervention,  reduce the bridge population connecting MSM network, establish social support system of homosexuality, and reduce the risk of HIV infection in MSM.