Background <p>Acute kidney injury (AKI) is a significant health concern in hospitalized children and is associated with increased mortality. However, the true burden of AKI-associated mortality in pediatric populations remains unclear.</p> Objective <p>To determine the pooled incidence of mortality independently associated with AKI in hospitalized children globally.</p> Data sources <p>Medline and Embase were searched for studies published by March 2024.</p> Study eligibility criteria <p>The inclusion criteria encompassed observational studies involving hospitalized pediatric patients (&lt; 18 years old) with AKI. Only studies that identified AKI as an independent risk factor for increased mortality in multivariate analysis were considered.</p> Study appraisal and synthesis methods <p>Studies with at least 100 AKI patients were included in the meta-analysis. Two authors extracted data on the study and patients’ characteristics and mortality across AKI stages and assessed the risk of bias. We used a random-effects meta-analysis to generate pooled estimates of mortality.</p> Results <p>Analysis of 60 studies including 133,876 children with AKI revealed a pooled in-hospital mortality rate of 18.27% (95% CI: 14.89, 21.65). Mortality increased with AKI severity; 8.19% in stage 1, 13.44% in stage 2, and 27.78% in stage 3. Subgroup analyses showed no significant differences across geographical regions, income levels, or AKI definition criteria. The pooled post-discharge mortality rate was 6.84% (95% CI: 5.86, 7.82) in a 1–9-year follow-up period.</p> Conclusions <p>This meta-analysis demonstrates a substantial global burden of AKI-associated mortality in hospitalized children, with higher mortality rates in more severe AKI stages. These findings highlight the critical need for early detection and intervention strategies in pediatric AKI management.</p> Clinical trial number <p>Not applicable.</p>