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.