Background: Schistosomiasis is a parasitic disease caused by worms of the genus Schistosoma.rnAlmost 85% of infected individuals live in Africa. Infection among preschool-aged children (1-5rnyears) in endemic areas was underestimated and is currently excluded from preventivernchemotherapy because of limited data on safety and efficacy, and partly due to a common thoughtrnthat schistosomiasis is not common in preschool-aged children (PSAC). rnObjective: The aim of this study was to review evidences regarding the prevalence ofrnschistosomiasis and its treatment outcome among preschool aged children. rnMethods: PRISMA guideline was followed during the conduct and reporting of this systematicrnreview and meta-analysis. A comprehensive search was carried out from PubMed, Cochranernlibrary, Google scholar and HINARI for studies published till April 2020. Extracted data inrnpreliminary table from papers selected for full-text review and passed eligibility criteria. Qualityrnassessment was based on Hoy 2012 tool using 10 criteria addressing internal and external validity.rnRandom-effects model was used to pool measures of effects and to construct 95% confidencerninterval (CI) around the pooled effect sizes. In addition, subgroup analysis was conducted tornimprove the outcome. rnResults: 38 studies were eligible for final systematic review and meta-analysis. Among the totalrnof 19592 childrenâ€™s participated 18,509 examined and 5,143 were found to be infected with onernor more species of schistosomiasis yielding an overall prevalence of 27.7% (95% CI: 22.833.5%).rnrnAnd the result shows there is significant variability between studies (Heterogeneity Irnrn=98.252 with Chi-square =2002.59, DF 35 and a P-value < 0.001). The result of meta regressionrnshowed diagnosis method used and study year had contributed significantly to the heterogeneityrnstudy results. Regarding treatment outcome, the overall CR was 88.9% (95% CI: 83.5-92.7%) andrnERR 97.3% (95% CI: 95.4-98.5%). The result of meta regression showed diagnosis method usedrnand study year had contributed significantly to the heterogeneity of study results.rnConclusion: this systematic review and meta-analysis showed there was a moderate prevalence of rnschistosomiasis and also good treatment outcome of praziquantel in preschool-aged children;rnindicating to review strategies to consider these age groups in mass drug administrationrndeworming programs until proper formulation accessible. rn2