Background: Human papillomavirus (HPV) is responsible for most cervical cancer cases globally, with women living with HIV having a higher risk of persistent HPV infection and HPV-associated disease. The HPV vaccine is a promising tool to reduce cervical cancer rates, but its uptake among women living with HIV in Nigeria is unknown. Methods: A facility-based, cross-sectional survey was conducted with 1371 women living with HIV to assess their knowledge of HPV, cervical cancer, and the HPV vaccine as well as their willingness to pay for the vaccine at the HIV treatment clinic at the Nigerian Institute of Medical Research, Lagos. To identify factors associated with the willingness to pay for the HPV vaccine, multivariable logistic regression models were developed. Results: This study found that 79.1% of participants had not heard of the vaccine, and only 29.0% knew its efficacy in preventing cervical cancer. In addition, 68.3% of participants were unwilling to pay for the vaccine, and the average amount they were willing to pay was low. Knowledge of HPV, the HPV vaccine, and cervical cancer and income were factors associated with the willingness to pay for the vaccine. Health workers were the primary source of information. Conclusions: This study highlights the lack of knowledge and low willingness to pay for the HPV vaccine among women living with HIV in Nigeria and emphasizes the importance of improving education and awareness. Factors associated with the willingness to pay, such as income and knowledge, were identified. Practical strategies, such as community outreach and school-based education programs, could be developed to increase vaccine uptake. Further research is needed to explore additional factors influencing the willingness to pay.