ABSTRACTObjective: To determine the psychosocial correlates of substance use among secondaryschool students in rural and urban communities in South Western Nigerian.Design: A cross-sectional survey of secondary school students using questionnaireeliciting substance use by students (WHO drug use questionnaire) and a well designedquestionnaire on psychosocial variables.Setting: Six secondary schools selected from two local government areas in Ilesa, OsunState, South Western Nigeria.Subjects: The study population comprised of 600 randomly selected senior secondaryschool students from six schools.Results: A total of 662 questionnaires were analysed. Current stimulant use was,significantly associated with lower socio-economic status, coming from 2 polygamousfamily arid self rated poor academic performance. Current alcohol use was associatedwith being a male, polygamous family background, living alone or with friends, notbeing religious arid self rated poor academic performance. Current hypnosedatives usewas commoner in students living alone or. with friends and in those with self ratedpoor academic performance. There was also significant positive relationship betweencurrent tobacco use and the male sex, not being religious and self rated poor academicLifetime use of these substances had similar association with the psychosocial variableswith slight differences.Conclusion: The similarity between the psychosocial correlates highlighted in this studyand those reported in Previous studies from other- parts of Nigeria makes theseobservations useful enough for the planning of preventive strategies