ObjectiveTo explore the impact of sports on aggression in children and adolescents and analyze whether different conditions in the intervention, such as type of sports, or intervention duration, have different influences on the effect of interventions.MethodThe study protocol was registered in PROSPERO (CRD42022361024). We performed a systematic search of Pubmed, Web of Science, Cochrane library, Embase and Scopus databases from database inception to 12 October 2022 for all studies written in English. Studies were included if they met the following PICO criteria. All analyses were carried out using the Review Manager 5.3 Software. We summarized aggression, hostility and anger scores using SMDs. Summary estimates with 95% confidence intervals were pooled using DerSimonian-Laird random effects model or fixed effects model according to between-study heterogeneity.ResultsA total of 15 studies were deemed eligible for inclusion in this review. The overall mean effect size indicated that sport interventions was associated with lower aggression (SMD = −0.37, 95% CI [−0.69 to −0.06],P= 0.020;I2= 88%). Subgroup analyses showed that non-contact sports were associated with lower aggression (SMD = −0.65, 95% CI [−1.17 to −0.13],P= 0.020;I2= 92%) but high-contact sports were not (SMD = −0.15, 95% CI [−0.55 to 0.25],P= 0.470;I2= 79%). In addition, when intervention duration <6 months, sport interventions was associated with lower aggression (SMD = −0.99, 95% CI [−1.73 to −0.26],P= 0.008;I2= 90%) and when intervention duration ≥ 6 months, sport interventions was not associated with lower aggression (SMD = −0.08, 95% CI [−0.44 to −0.28],P= 0.660;I2= 87%).ConclusionThis review confirmed that sports intervention can reduce the aggression of children and adolescents. We suggested that schools can organize young people to participate in low-level, non-contact sports to reduce the occurrence of bullying, violence and other aggression-related adverse events. Additional studies are needed to determine which other variables are associated with aggression in children and adolescents, in order to develop a more detailed and comprehensive intervention programme to reduce their aggression.