Objectives: To systematically review and quantitatively synthesize the evidence for the impact of different types of school-based interventions on the reduction of school exclusion. Methods: A systematic search of 27 databases including published and unpublished literature was carried out between September and December 2015. Eligible studies evaluated interventions intended to reduce the rates of exclusion; targeted children from ages four to 18 in mainstream schools; and reported results of interventions delivered from 1980 onwards. Only randomised controlled trials were included. Two independent reviewers determined study eligibility, extracted data and rated the methodological quality of studies. Results: Based on the thirty-seven studies eligible for meta-analysis, under a random effects model, results showed that school-based interventions significantly reduced school exclusion during the first six months after implementation SMD=.30, 95% CI [.20, .41], p<.001. The impact at follow-up (i.e., 12 or more months) was reduced by half and it was not statistically significant. Heterogeneity was mainly explained by the role of the evaluator: independent evaluators reported lower effect sizes than researchers involved in the design and/or delivery of the intervention. Four approaches presented promising and significant results in reducing exclusion: enhancement of academic skills, counselling, mentoring/monitoring, and skills training for teachers. Conclusions: Results suggest that school-based interventions can be effective in reducing school exclusion in the short term. Some specific types of interventions show more promising and stable results, but, based on the small number of studies involved in our calculations, we suggest that results are interpreted with caution.