BackgroundPsychiatric disorders had been reported with higher prevalence among people living with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), [PLWHA] than the general population and its presence could confer poorer prognosis on infected individuals. However, there is limited research on the above subject matter in the North-Central part of Nigeria. Thus, this study aimed to determine the prevalence of common psychiatric disorders (CPD) among adult out-patients PLWHA at the University of Ilorin Teaching Hospital (UITH), Ilorin, North-Central Nigeria.MethodsIt was a hospital-based descriptive cross-sectional study, conducted among 363 respondents attending the UITH Highly Active Antiretroviral Therapy (HAART) clinic between March and May 2019. Interviewer-administered questionnaires were used to collect data. Mini International Neuropsychiatric Interview (MINI) was used to assess the prevalence of CPD among respondents. Data were analysed using the Statistical Package for Social Sciences version 21 and p value of < 0.05 was taken as statistically significant.ResultsThe prevalence of depression was 24.5%, anxiety disorder (AD) was 16.8% and alcohol use disorder (AUD) was 0.6%. Respondents from the extended family type were more depressed 70.4% and about half 43.3% of the nuclear family had AD while a 1.6% prevalence of AUD was found among the nuclear family. The association was statistically significant with a p value of 0.001.ConclusionCPD exist among PLWHA with increasing prevalence therefore screening for these disorders should be encouraged during routine management of PLWHA to improve their psychological well-being.