International Journal of Preventive Medicine (Int J Prev Med)2008-78021292021102025222522ENM.sc. in Health Services Management, Lecture, School of Public Health, Social Determinates of Health Research Center, Yasuj University of Medical Sciences, YasujAssistant Professor of Psychiatry, School of Medicine, Psychosocial Injuries Research Center, Shahid Mostafa Khomaeini Hospital, Ilam University of Medical sciences, IlamResearch Center for Environmental Determinants of Health, School of Public Health, Kermanshah University of Medical Sciences, KermanshahTraditional and Complementary Medicine Research Center, Addiction Institute, Mazandaran University of Medical Sciences, SariSocial Determinants of Health Research Center, School of allied medical sciences, Shahrekord University of Medical Sciences, Shahrekord20211019Background: Depression is one of the major psychiatric disorders in the world. The present study was conducted to determine the prevalence of depression among Iranian school students through a meta‑analysis. Methods: All national and international information databases including PubMed, Scopus, Web of Science, SID, Magiran, Medlib were searched. The search phase was performed without language and time restrictions, but the searched studies were all in Persian and English, and the sources were updated by 03.08.2020. As the selected studies had high heterogeneity, the random effects model was used. Results: In 51 studies with a sample of 537144 people, the prevalence of depression in Iranian school students was 37% (95%CI: 32, 42). In addition, the prevalence of depression in girl school students was 45% (95%CI: 25‑65) and in boys was 28% (95%CI: 20‑35). The prevalence of mild, moderate and severe depression in school students is 31%, 18% and 11%, respectively. Also, the prevalence of depression in primary school students was 12%, middle school students 32%, high school students 47% and pre‑university students 46%. Conclusions: About a third of Iranian school students suffer from some degree of depression, and the prevalence of depression in girls is about twice that of boys. The prevalence of mild depression among school students is higher than moderate and severe depression. On the other hand, the prevalence of depression in school students from primary to pre‑university level is increasing, which is very worrying.http://ijpm.mui.ac.ir/index.php/ijpm/article/view/2522http://ijpm.mui.ac.ir/index.php/ijpm/article/download/2522/717718363