BACKGROUND: Risk factors for acute kidney injury (AKI) in pediatric patients after hematopoietic stem cell transplantation (HSCT) remain controversial. OBJECTIVES: This study aimed to identify risk factors for AKI following HSCT in the pediatric population. DATA SOURCES: PubMed, Embase, Web of Science, Cochrane Library, and Scopus databases were searched from inception to February 8, 2023. STUDY ELIGIBILITY CRITERIA: Studies meeting the following criteria were included: (1) The study was a case-control, cohort study, or cross-sectional design, (2) the study was performed among pediatric and young patients aged 21 years or younger undergoing HSCT, (3) the study measured at least one related factor for AKI after pediatric HSCT, (4) the study included a sample of at least ten patients, and (5) original articles published in English in peer-reviewed scientific journals. PARTICIPANTS AND INTERVENTIONS: Children who were undergoing pediatric HSCT. STUDY APPRAISAL AND SYNTHESIS METHODS: We assessed the quality of the included studies and analyzed them with a random-effect model. RESULTS: Fifteen studies with a total of 2,093 patients were included. All were cohort studies of high quality. The overall pooled incidence of AKI was 47.4% (95%CI 0.35, 0.60). We found significant associations between post-transplant AKI in pediatric patients and unrelated donor [odds ratio (OR) = 1.74, 95% confidence interval (CI) 1.09-2.79], cord blood stem cell transplantation (OR = 3.14, 95%CI 2.14-4.60), and veno-occlusive disease (VOD)/sinusoidal obstruction syndrome (SOS) (OR = 6.02, 95%CI 1.40-25.88). Other controversial factors such as myeloablative conditioning (MAC), acute graft vs. host disease (aGVHD), and the use of calcineurin inhibitors (CNI) were not found to be related to AKI after pediatric HSCT. LIMITATIONS: Results were limited mainly by heterogeneity in the characteristics of patients and transplantation. CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS: Posttransplant AKI in children is a common complication. Unrelated donors, cord blood stem cell transplantation, and VOD/SOS might be risk factors for AKI after pediatric HSCT. Further large-scale studies are still needed to draw firm conclusions. SYSTEMATIC REVIEW REGISTRATION NUMBER: CRD42022382361 A higher resolution version of the Graphical abstract is available as Supplementary information.