Abstract: Objective To understand the prevalence of hepatitis B virus (HBV) infection and related risk factors among HIV-infected adults in Dehong, Yunnan province. Methods A cross-sectional study was carried out among HIV-infected adults in Dehong and serum tests were performed to detect HBV infection related markers. Results A total of 5732 HIV infected adults were included in this study, the positive rates of HBsAg, HBsAb, HBeAg, HBeAb, HBcAb were 8.5%, 47.7%, 1.8%, 9.1%, and 65.0%, respectively. The positive rate of HBsAg, HBeAg and HBcAb was 1.6%, Multivariate logistic regression analysis indicated that the risk of HBV infection was higher in those aged 18-29 years than in those aged 50 years (OR=3.04,95% CI:1.30-7.15), in males than in females (OR=1.77,95% CI:1.06-2.95) among the HIV infected adults surveyed. Conclusion The co-infection of HBV was prevalent in HIV-infected adults in Dehong and related with demographic characteristics.