This study examines the effect of family structure on adolescent delinquency in Ifo local government area of Ogun State, Nigeria. The main purpose of the study is to determine the effect of family cohesion on adolescent delinquency. A total number of 400 heads of household were selected and interviewed through a systematic random sampling technique using structured questionnaires. Focus group discussions (FGD) were also conducted to derive an in-depth knowledge on how family structure affected the behavior of the children. Three levels of data analyses were employed. At the multivariate level, the logistic regression model was used to estimate odds ratios for each of the indicators of delinquent behaviour considered in the analyses.