Introduction: as the coronavirus disease 2019 (COVID-19) vaccines are distributed and administered globally, hesitancy towards the vaccine hinders the immunisation of a significant number of vulnerable populations, such as people living with HIV/AIDS. Hence, this study aims to assess COVID-19 vaccine hesitancy among people living with HIV/AIDS (PLHIV) attending clinical-outpatient follow-up at State Specialist Hospital Maiduguri (SSHM), Borno State, Nigeria. Methods: a hospital-based cross-sectional study design was conducted to assess COVID-19 vaccine hesitancy among 344 PLHIV receiving antiretroviral therapy (ART) at the United States President´s Emergency Plan for AIDS (PEPFAR) clinic in SSHM from 4th January to 25th February 2022. Data were collected using a structured and pretested interviewer-administered questionnaire. The results were presented using frequencies and percentages. The factors that are associated with COVID-19 vaccine hesitancy were identified using the Chi-square statistical test. Results: among the 344 respondents of the study, only 88 (26.6%) received the COVID-19 vaccine. Out of the 256 respondents that did not receive the vaccine, only 10.5% (27/256) are willing to be vaccinated, while the majority; 57.8% (148/256) are not willing to be vaccinated and 31.7% (81/256) of the respondents are uncertain, thus resulting in a hesitation rate of 89.45%. There was no statistically significant association between COVID-19 vaccine hesitancy and the study´s independent variables; where p-value is greater than 0.05. Conclusion: hesitancy towards COVID-19 vaccine is high among PLHIV and there is no any statistically significant association between COVID-19 vaccine hesitancy and the independent variables of the study where p-value is greater than 0.05. Hence, it is necessary to develop targeted strategies to boost vaccine uptake among this vulnerable population.