Abstract: Objective To investigate the HIV infection among men who have sex with men (MSM) in Wanzhou, Chongqing, and analyze its risk factors. Methods From January to December 2020, 349 men with same-sex sexual behavior of oral or anal sex within one year were recruited in Wanzhou, Chongqing were recruited through peer introduction, social organization outreach intervention and referral, QQ group, wechat group and other social platforms. Collect the factors that may affect the HIV infection of MSM population through questionnaire, take blood test for all respondents, and divide the respondents into HIV positive group and HIV negative group according to the HIV infection.The factors collected by the questionnaire were compared between the two groups of survey subjects, and the multi-factor Logistic regression analysis was used to determine the comprehensive impact of each factor on the HIV infection in the MSM population. Results 349 questionnaires were distributed and 342 valid questionnaires were recovered, with a recovery rate of 97.99%. A total of 21 people (6.14%) were diagnosed with HIV infection. Multivariate Logistic regression analysis showed that age（OR=1.436,95%CI=1.015~2.032）, drinking history（OR=1.446,95%CI=1.053~1.987）, drug use history（OR=1.517,95%CI=1.081~2.130 ）, sex role No.0（OR=1.536,95%CCI=1.129~2.089）, occasional condom use or no condom use in recent 6 months（OR=1.505,95%CI=1.075~2.109）, commercial sex history in recent 6 months（OR=1.465,95%CI=1.040~2.065）, sexual history（OR=1.670,95%CI=1.165~2.396）, number of sexual partners >1（OR=1.525,95%CI=1.045~2.226）, and use of booster（OR=1.507,95%CI=1.042~2.178）were risk factors for HIV infection among MSM in Wanzhou, Chongqing (P<0.05). Conclusion The HIV infection rate of MSM population in Wanzhou, Chongqing is high. The HIV infection of this population is mainly affected by age, education level, drinking history and other factors. Targeted intervention can be carried out according to the above factors to reduce the HIV infection rate of MSM population.

Key words: Men who have sex with men, HIV infection, Risk factor