This study aimed to assess HPV vaccine uptake and its predictors among adolescent girls and young women living with HIV. We analyzed cross-sectional baseline data from a pilot randomized controlled trial involving 100 girls and young women (aged 10-24 years) living with HIV and receiving care in Uganda's Greater Masaka region. The study was conducted in four Antiretroviral(ART) providing healthcare facilities between January and March 2024. Surveys were used to collect data on socio-demographics (age, religion, education), HPV acceptability, barriers to vaccination, perceived susceptibility, knowledge about HPV and cervical cancer, and HPV vaccine uptake. We then conducted a logistic regression analysis to determine the predictors of HPV vaccine uptake. We also tested assumptions for the logic regression. The health belief model guided us in selecting the variables to include in the final logistic regression model. The findings revealed a low vaccine uptake rate, with only 31% vaccinated participants. Significant predictors included sexual experience (OR = 4.08, p = 0.011) and HPV knowledge (OR = 1.41, p = 0.016). Participants without sexual experience were four times more likely to be vaccinated, and higher HPV knowledge increased the likelihood of vaccination. However, perceived barriers, susceptibility, and cervical cancer knowledge were not significant predictors. These findings highlight the need to address barriers and improve HPV knowledge to enhance vaccine uptake, particularly among adolescent girls and young women living with HIV.