Abstract Background The incidence of hemostatic complications in pediatric patients undergoing extracorporeal membrane oxygenation (ECMO) is high. The optimal anticoagulation strategy in children undergoing ECMO is unknown. Objectives To study the association between hemostatic complications, coagulation tests, and clinical parameters in pediatric patients undergoing ECMO and their effect on survival. Methods We performed a retrospective cohort study of pediatric patients undergoing centrifugal pump ECMO. Collected data included patient characteristics, risk factors, and coagulation test results. Statistical analysis was done using logistic regression analysis for repeated measurements. Dependent variables were thrombosis and bleeding, independent variables were rotational thromboelastometry (ROTEM), activated partial thromboplastin time (aPTT) and antifactor‐Xa assay (aXa) results, ECMO duration, age