ABSTRACT: Importance:Reliable estimates of the prevalence of childhood hypertension serve as the basis for adequate prevention and treatment. However, the prevalence of childhood hypertension has rarely been synthesized at the global level. Objective:To conduct a systematic review and meta-analysis to assess the prevalence of hypertension in the general pediatric population. Data Sources:PubMed, MEDLINE, Embase, Global Health, and Global Health Library were searched from inception until June 2018, using search terms related to hypertension (hypertension OR high blood pressure OR elevated blood pressure), children (children OR adolescents), and prevalence (prevalence OR epidemiology). Study Selection:Studies that were conducted in the general pediatric population and quantified the prevalence of childhood hypertension were eligible. Included studies had blood pressure measurements from at least 3 separate occasions. Data Extraction and Synthesis:Two authors independently extracted data. Random-effects meta-analysis was used to derive the pooled prevalence. Variations in the prevalence estimates in different subgroups, including age group, sex, setting, device, investigation period, BMI group, World Health Organization region and World Bank region, were examined by subgroup meta-analysis. Meta-regression was used to establish the age-specific prevalence of childhood hypertension and to assess its secular trend. Main Outcomes and Measures:Prevalence of childhood hypertension overall and by subgroup. Results:A total of 47 articles were included in the meta-analysis. The pooled prevalence was 4.00% (95% CI, 3.29%-4.78%) for hypertension, 9.67% (95% CI, 7.26%-12.38%) for prehypertension, 4.00% (95% CI, 2.10%-6.48%) for stage 1 hypertension, and 0.95% (95% CI, 0.48%-1.57%) for stage 2 hypertension in children 19 years and younger. In subgroup meta-analyses, the prevalence of childhood hypertension was higher when measured by aneroid sphygmomanometer (7.23% vs 4.59% by mercury sphygmomanometer vs 2.94% by oscillometric sphygmomanometer) and among overweight and obese children (15.27% and 4.99% vs 1.90% among normal-weight children). A trend of increasing prevalence of childhood hypertension was observed during the past 2 decades, with a relative increasing rate of 75% to 79% from 2000 to 2015. In 2015, the prevalence of hypertension ranged from 4.32% (95% CI, 2.79%-6.63%) among children aged 6 years to 3.28% (95% CI, 2.25%-4.77%) among those aged 19 years and peaked at 7.89% (95% CI, 5.75%-10.75%) among those aged 14 years. Conclusions and Relevance:This study provides a global estimation of childhood hypertension prevalence based on blood pressure measurements in at least 3 separate visits. More high-quality epidemiologic investigations on childhood hypertension are still needed.