 The study aimed to understand the uptake of COVID-19 vaccine and factors associated with vaccine hesitancy among HIV-infected men who have sex with men, MSM, in mainland China. The results showed that the uptake of COVID-19 vaccine was 8.7% with concern about side effects and disclosure of HIV infection being the top reasons for not initiating vaccination. Men who had high antiretroviral therapy adherence paid attention to information about the COVID-19 vaccine, preferred domestic vaccines, thought the pandemic had moderate or moderately severe impact on immunity, were waiting for workplace-organized vaccination programs, and were unaware of where to get the vaccine had lower degree of COVID-19 vaccine hesitancy. Men who were concerned about the efficacy and side effects of the vaccine had higher degree of vaccine hesitancy. The study suggests that understanding influencing factors of vaccine hesitancy among this group and making tailored measures to alleviate hesitancy would help improve the coverage of COVID-19 vaccination in this population.