This study examines the relationship between student substance use and school-level parental involvement as reported by administrators. Questionnaires were administered to school administrators and 111,652 students in 1,011 U.S. schools. Hierarchical logistic regression analyses conducted on 1998-2003 data from students and administrators indicate significantly lower prevalence of alcohol use among eighth-graders in schools where administrators reported high parental involvement. Overall, administrators' reports of high parental involvement were unrelated to prevalence of substance use among tenth-graders and were associated with higher prevalence of alcohol use among twelfth-graders. Implications and limitations are discussed, along with suggestions for future research.