This study explored the relations between parental problem drinking, adolescent–parent communication, and adolescent psychosocial adjustment. Surveys were administered to a diverse sample of 683 15–17-years-old adolescents in the spring of 2007 and again in the spring of 2008. Results indicated that paternal problem drinking directly predicted substance use (alcohol and drug use) for boys, but not for girls. In contrast, maternal problem drinking directly predicted substance use (drug use) for girls, but not for boys. Adolescent–parent communication also mediated the relationship between parental problem drinking and psychosocial adjustment for girls, but not for boys. These gender differences highlight the need to consider both the gender of the adolescent and the parent when examining parental problem drinking and adolescent adjustment.