Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a bridging therapy for refractory cardiogenic shock, and limb ischemia is a concern with femoral cannulation. Because of the rich collateral pelvic circulatory supply, buttock ischemia is not common and is usually a complication after aneurysmal aortic repair or internal iliac artery embolization after pelvic trauma. Gluteal necrosis occurring as an extracorporeal membrane oxygenation complication has not been reported in the literature. In this case series, we report three patients with ischemic buttock after initiating VA-ECMO and discuss the risk factors and the clinical and radiological features supportive of the diagnosis. We review the gluteal and pelvic vascular anatomy, postulate how cannula size, ethnicity, catecholamines, and reversal of gluteal arterial flow contributed to this rare entity in our patients and explain how these findings have changed our institution's practice.