Background: The purpose of the present study was to test components of Raine's (2002) biosocial model, specifically the interactive effects of perinatal complications, rejecting parenting, and family adversity on the development of early-onset antisocial behavior (ASB). Boys' internalizing problems were also tested to investigate the specificity of the model. Methods: Birth records in addition to longitudinal data were collected on 310 low-income boys followed from birth until 10 years of age. Results: Findings demonstrated support for a biosocial framework in predicting ASB but not internalizing problems. Family adversity, and to some extent rejecting parenting, consistently predicted youth outcome. Perinatal complications emerged as a predictor of ASB but only in the context of other family risk factors. According to maternal report, boys experiencing high levels of perinatal complications, rejecting parenting, and family adversity showed significantly higher levels of ASB than boys with lower levels of these risk factors. This finding was partially corroborated by youth self-report, such that boys experiencing high levels of perinatal complications and family adversity reported more antisocial activity than boys experiencing no risk or risk in only one domain. Conclusions: This study supports the specific prediction of ASB in middle childhood from a biosocial model. Findings also highlight the salience of a negative psychosocial environment on childhood maladjustment. Intervention efforts including parenting skills and coping strategies for mothers of children from multiple risk environments are advocated.