ObjectiveTo determine the trend and influencing factors of HIV subtypes in newly reported HIV/AIDS cases in Dehong Dai and Jingpo Autonomous Prefecture (Dehong Prefecture) from 2017 to 2019.MethodsRNA extraction was conducted among newly reported HIV/AIDS cases in Dehong Prefecture from 2017 to 2019 whose plasma volume was more than 200 μL. The gag, env and pol genes were amplified by using RT-PCR and then sequenced to determine the subtypes.ResultsA total of 3 287 HIV-infected cases were newly reported in Dehong from 2017 to 2019. The HIV gag, env and pol genotypes were determined in 1 813 cases. The major subtypes were subtype C (28.4%,515/ 1 813), recombination form BC (22.0%,398/1 813) and CRF_01AE (18.1%,329/1 813). Furthermore, the proportion of subtype B, subtype C and CRF01_AE decreased over years, whereas 01/BC, CRF07_BC and CRF08_BC increased over years in both Chinese and Burmese patients (χ2=75.212,P