We investigated the association between parental factors (including infection with human immunodeficiency virus [HIV], acquired immunodeficiency syndrome [AIDS] diagnosis, parental medical illness, and depression) and children's behavioral and emotional problems among children of injection drug users (IDUs). IDUs were recruited through community outreach. The sample included 73 parents of 73 children, aged 4 to 12 years. Parental depression (odds ratio [OR] = 4.61) and medical illness (OR = 4.70) were found to be significantly associated with internalizing (depressive and anxiety-related symptoms), but not with externalizing (aggressive and disruptive behaviors) symptoms in the children of IDUs. The clinical implications are that children of IDUs are known to be at high risk for psychiatric symptoms and disorders; these data suggest that children of depressed and/or medically ill IDU parents may be at even higher risk of internalizing symptoms (depression and anxiety symptoms) than children of IDUs who do not suffer from these conditions.