Pediatric cardiac extracorporeal membrane oxygenation (ECMO) patients have high mortality rates. The purpose of our study was to develop and validate the Pediatric Survival After Veno-arterial ECMO (Pedi-SAVE) score for predicting survival at hospital discharge after pediatric cardiac veno-arterial (VA) ECMO. We used data for pediatric cardiac VA-ECMO patients from the Extracorporeal Life Support Organization registry (1/1/2001–12/31/2015). Development and validation cohorts were created using 2:1 random sampling. Predictors of survival to develop pre- and postcannulation models were selected using multivariable logistic regression and random forest models. ß-coefficients were standardized to create the Pedi-SAVE score. Of 10,091 pediatric cardiac VA-ECMO patients, 4,996 (50%) survived to hospital discharge. Pre- and postcannulation Pedi-SAVE scores predicted that the lowest risk patients have a 65% and 74% chance of survival at hospital discharge, respectively, compared to 33% and 22% in the highest risk patients. In the validation cohort, pre- and postcannulation Pedi-SAVE scores had c-statistics of 0.64 and 0.71, respectively. Precannulation factors associated with survival included: nonsingle ventricle congenital heart disease, older age, white race, lower STAT mortality category, higher pH, not requiring acid-buffer administration, <2 cardiac procedures, and indication for VA-ECMO other than failure to wean from cardiopulmonary bypass. Postcannulation, additional factors associated with survival included: lower ECMO pump flows at 24 hours and lack of complications. The Pedi-SAVE score is a novel validated tool to predict survival at hospital discharge for pediatric cardiac VA-ECMO patients, and is an important advancement in risk adjustment and benchmarking for this population.