Background <p>The use of manufactured tobacco cigarettes and e-cigarettes continues to be an important determinant of adverse health outcomes during adolescence, especially in Latin America, despite existing prevention policies. In Peru, there is a stabilization in cigarette consumption and a notable increase in the use of Electronic Nicotine Delivery Systems (ENDS), which requires new explanatory studies. Based on the Theory of Planned Behavior, the aim was to analyze how subjective norms and attitudes toward tobacco predict the intention and subsequent consumption of manufactured and e-cigarettes among Peruvian adolescents.</p> Methods <p>This was a cross-sectional study using secondary data from the Global Youth Tobacco Survey 2019 in Peru. The sample included 2593 school adolescents aged 13 to 15 from different regions of the country. Structural Equation Modeling was applied to evaluate a partial version of the Theory of Planned Behavior including the effects of exposure to tobacco consumption in environments close to adolescents such as the home, school, and other settings (descriptive subjective norms), as well as attitudes toward tobacco on the intention to use tobacco products, and the predictive effect of this intention on frequency of manufactured and e-cigarette consumption. Perceived Behavioral Control was not included in the model due to an insufficient number of indicators.</p> Results <p>Exposure to tobacco consumption at home and in adolescents’ everyday environments was a significant predictor of the intention to use tobacco products, whereas exposure at school showed a weaker and not significant effect. Negative attitudes toward tobacco predicted lower intention, indicating a protective cognitive factor. Together, these variables explained 32% of the variance in the intention to consume tobacco. In turn, the intention to use tobacco products was significantly associated with both manufactured cigarette use and e-cigarette use, with a stronger predictive effect for manufactured cigarettes than for e-cigarettes, explaining 79% and 37% of their variance, respectively.</p> Conclusions <p>Manufactured and e-cigarette consumption among Peruvian adolescents represents distinct behavioral outcomes that merit examination in relation to antecedents such as tobacco-related use intention, social norms, and attitudes. Preventive interventions should address both the family and public environment while also targeting adolescents’ cognitive perceptions about tobacco, especially in a context of increasing e-cigarette use.</p>