Children undergoing cardiac surgical procedures may require postoperative surgical or catheter-based reintervention before discharge. We examined racial/ethnic variations in reintervention and associated in-hospital death.Children undergoing cardiac surgical procedures from 2004 to 2015 were identified in the Pediatric Health Information Systems (PHIS) database. Regression analysis measured associations between race/ethnicity, in-hospital death, and postoperative cardiac surgical or catheter-based reintervention (surgical/catheter reintervention).Of 124,263 patients, 8265 (6.7%) had a surgical/catheter reintervention. Black patients had fewer reinterventions (5.9% vs 6.7%) and higher in-hospital mortality (3.9% vs 2.7%, P < .01) than White patients. After adjusting for sociodemographic and illness severity indicators, Black patients remained less likely to receive surgical/catheter reintervention (adjusted hazard ratio [aHR], 0.89; 95% CI, 0.82-0.98) despite having similar risk of death after reintervention (adjusted odds ratio, 1.17; 95% CI, 0.98-1.41) compared with White patients. The risk of death without surgical/catheter reintervention was also higher for Black (aHR, 1.26; 95% CI, 1.08-1.47) and other race/ethnicity (aHR, 1.33; 95% CI, 1.13-1.57) patients than for White patients. Similar trends were demonstrated when mechanical circulatory support and cardiac transplantation were included as reinterventions.Patients of Black and other race/ethnicity undergoing pediatric cardiac surgical procedures are more likely to die without postoperative cardiac reintervention than White patients. Black patients are also less likely to receive reintervention despite no significant difference in mortality with reintervention. Further studies should evaluate etiologies and methods of addressing these disparities.