Two cross-sectional studies investigated media influences on adolescents' substance use and intentions to use substances in the context of exposure to parental and peer risk and protective factors. A total of 729 middle school students (n = 351, 59% female in Study 1; n = 378, 43% female in Study 2) completed self-report questionnaires. The sample in Study 1 was primarily African-American (52%) and the sample in Study 2 was primarily Caucasian (63%). Across the two studies, blocks of media-related cognitions made unique contributions to the prediction of adolescents' current substance use and intentions to use substances in the future above and beyond self-reported peer and parental influences. Specifically, identification with and perceived similarity to media messages were positively associated with adolescents' current substance use and intentions to use substances in the future, and critical thinking about media messages and media message deconstruction skills were negatively associated with adolescents' intention to use substances in the future. Further, peer influence variables (e.g., peer pressure, social norms, peer substance use) acted as risk factors, and for the most part, parental influence variables (e.g., parental pressure to not use, perceived parental reaction) acted as protective factors. These findings highlight the importance of developing an increased understanding of the role of media messages and media literacy education in the prevention of substance use behaviors in adolescence.