摘要:Background: Adolescence is considered as a momentous period for initiating risky behaviors. Adolescents do not have an accurate understanding of the perilous consequences of their behavior due to being self-centered. They are likely to discover risky situations, which increases their capacity for danger. The purpose of this systematic review study is to evaluate the school-based educational interventions to increase self-efficacy in preventing smoking in Iranian adolescents. Materials and Methods: In this systematic review, all experimental and quasi-experimental studies from January 2000 to April 2019 in Iran, were searched from Web of Science, Scopus, ProQuest, Cochrane Library, and Medline (via PubMed) as English databases and SID, IRCT, Magiran and Irondoc as Iranian databases. Keywords were selected based on the Mesh and include: "adolescent, teenager, student, smoking, cigarette, education and Iran" combined with the Boolean OR and AND operators. Two reviewers studied the full text of the articles and their main findings were extracted and categorized. Quality assessment of studies was checked and verified by two authors independently based on Cochrane tool. Results: In this systematic review, 6 studies with 964 adolescents that met the inclusion criteria were included in the study; 5 of them were published in English and 1 in Persian. Different methods of school education, including lectures, film presentations, group discussions, question and answer sessions and role playing were used in these studies. Conclusion: According to the results of this study, education of adolescents in the school environment is effective in increasing self-efficacy skills as a preventive measure of smoking in adolescents.