Adolescent alcohol and marijuana use pose significant developmental risks. This study examined internalizing and externalizing problems as risk factors and prospective self as a protective factor in relation to alcohol and marijuana use. Self-report data were collected from a diverse sample (N = 2017) of 15-17-year-olds using the Youth Self Report (YSR) for behavior issues and Prospective Self, a factor derived variable reflecting future orientation, resistance to peer influence, and academic aspirations. Participants reported on 15 health risk behaviors, including alcohol and marijuana use. Weighted linear regressions evaluated associations between risk and protective factors and substance use. Model 1 included sociodemographic covariates. Model 2 added risk and protective factors, and Model 3 included interactions of internalizing and externalizing behaviors with prospective self. Results indicated higher externalizing behavior was linked to increased alcohol and marijuana use, while higher prospective self and internalizing behavior were linked to reduced alcohol use. Higher prospective self was associated with less marijuana use. Interaction terms were largely non-significant, except for the interaction between prospective self and internalizing behavior, where higher internalizing problems and high prospective self were linked to increased marijuana use. Findings highlight the importance of prospective self, especially at clinically elevated levels of behavior problems, and suggest further exploration of the unexpected positive association between internalizing behavior and prospective self with marijuana use.