Despite the common perception of a decline over recent decades of adolescents' use of illicit drugs and alcohol, the recent exponential rise in teenage vaping has spotlighted how local and school communities must address this endemic public problem. Since use of illicit substance adversely affects adolescent development, it is imperative that educators assess the prevalence of drugs and alcohol and curtail access in secondary schools. We examined the association between drug and alcohol availability and school security measures, using data from the 2015 National Criminal Victimization Survey School Crime Supplement. Logistic regression determined whether school security measures (inclusive, exclusive, and ambiguous) reduce student-perceived drug and alcohol availability in U.S. secondary schools. Our findings indicated that students in secondary schools with school resource officers perceived greater drug and alcohol availability, while locked doors were associated with lower perceived availability. No inclusive security measures were associated with increased or decreased drug and alcohol availability. Only one exclusive measure -- locker checks -- in a single model related to perceived marijuana availability was significantly associated with perceived lower substance availability. School leaders and policy makers should consider the effectiveness of security measures to reduce substance use, while ascertaining the likelihood of detrimental effects.