Objective To understand the effectiveness of antiviral treatment for AIDS patients and drug resistance situation in treatment failures in Inner Mongolia Autonomous Region.Methods The data on viral load detection of HIV infection and AIDS patients(HIV/AIDS)who received antiviral treatment for ≥ 6 months were collected from the National AIDS Integrated Prevention and Treatment Information System in the Inner Mongolia Autonomous Region up to December 31,2022,to analyze the factors influencing the failure of HIV/AIDS virus suppression and drug resistance situation.Results Of 6 088 patients,368(6.04%)had a viral load ≥ 1 000copies/ml(antiviral treatment failure).The education level,route of infection,CD4+T lymphocyte count and treatment time were the treatment failure of HIV/AIDS virus inhibition,and the differences were statistically significant(x2=13.223,11.869,390.093,1 493.862,P<0.05).Multivariate analysis showed that education level,CD4+T lymphocyte count and treatment time were associated with antiviral treatment failure.Of the 151 sequences obtained,83(54.97%)and 56(37.09%)were resistant to non-nucleoside reverse transcriptase inhibitors(NNRTIs)and nucleoside reverse transcriptase inhibitors(NRTIs),respectively.The resistant mutant strains were mainly CRF01_AE(52.75%)and CRF07_BC(21.98%).Conclusion The effectiveness of antiviral treatment of HIV/AIDS in Inner Mongolia Autonomous Region is relatively good,and the incidence of drug resistance of HIV/AIDS with treatment failure is high.Drug management and drug resistance monitoring should be strengthened.