Background: Overweight is a serious nutritional problem in children. Currently, overweight is a nutritional problem in all countries, both developed and developing countries. One of the efforts to stop increasing overweight in children is to provide school-based interventions. This study aims to estimate the magnitude of the effect of school-based interventions on overweight in children based on a number of previous primary studies.Subjects and Method: Meta-analysis was performed by systematically reviewing articles from Google Scholar, PubMed, BMJ, ScienceDirect, BMC, and Sage. The articles used in this research are articles that have been published from 2007-2018. Keywords for searching articles are as follows: (preschool OR school) AND (intervention OR program prevention) AND ("children obesity" OR "children overweight") AND "randomized control trials" and "preschool based" OR "school based" AND intervention OR prevention OR program AND "childhood obesity" OR "childhood overweight" OR "children obesity" OR "children overweight". The inclusion criteria used were full paper, used English, randomized controlled trials study design and the results reported Risk Ratio (RR). Articles are collected using PRISMA diagrams and analyzed using the Review Manager 5.3 application.Results: A total of 10 articles were reviewed in this study. Between experimental groups were homogeneous (I2= 0%; p= 0.570), therefore this study was conducted using a fixed effect model. Studies show that school-based interventions have the effect of reducing the BMI of overweight children (RR = 0.89; 95% CI = 0.82 to 0.97; p = 0.007) in China, the United States, Mexico, Germany, Portugal, France, and the UK.Conclusion: School-based interventions have the effect of reducing the risk of overweight in children in China, the United States, Mexico, Germany, Portugal, France, and the UK.Keywords: School-based intervention, overweight childrenCorrespondence: Riftiani Nikmatul Nurlaili. Masters Program in Public Health, Universitas Sebelas Maret, Jl. Ir. Sutami 36A, Surakarta 57126, Central Java. Email: riftiani.nurlaili@gmail.com. Mobile: 085746737137.Journal of Maternal and Child Health (2020), 05(06): 683-392https://doi.org/10.26911/thejmch.2020.05.06.08.