Abstract: Objective To make sure the HIV-1 drug resistance mutations rate in man who had sex with man in Liaoning province.Methods Totally 46 samples from antiretroviral therapy-naive MSMs were collected.The entire protease gene and 1～250 amino acids of the reverse transcriptase gene were amplified by RT-PCR and nested PCR from genome RNA and sequenced.The results were analyzed with HIVdb-Drug Resistance Algorithm and genotypic resistance mutations were determined to particular anti-HIV drugs.Results One subtype BHIV-1 infected case carried L90M,a major mutation against protease inhibitors.Another CRF-01AE HIV-1 infected case carried M46 I,a major mutation against protease inhibitors.Other cases carried only minor mutations:3 cases carried L10 I,1 case carried A71 T.None mutation against reverse transcriptase inhibitors was detected.Conclusion HIV-1 drug resistance strain transmission was found in MSMs in Liaoning province.