Research concerning hypothesized relationships between parental alcoholism and conduct problems in their children has had mixed findings. In this study, general and specific aspects of a possible relationship between a history of parental substance abuse (a category including parental alcohol abuse and parental abuse of other substances) with antisocial behavior and severe aggressive/destructive behavior was studied by reviewing preadmission variables in a large group of hospital‐treated children and adolescents. The results indicated that various categories of more specifically defined parental substance abuse (e.g., substance abuse in fathers) were related to severe aggressive/destructive behavior and/or conduct disorder in their children. Parental abuse of nonalcohol substances appears to be more important than parental alcohol abuse in predicting severe aggressive and antisocial behavior. Substance abuse in fathers, especially abuse of substances other than alcohol, also seems more important than substance abuse in mothers in predicting severe aggression and conduct disorde