The combination of hypothermia and potassium cardioplegic arrest has become the most common method of myocardial protection in the evolution of myocardial protection. This review focuses on myocardial protection in pediatric cardiac surgery. In the 1980s, blood was added to cardioplegia solution in order to supply the myocardium with oxygen, nutrients, and for buffering purposes. Similar myocardial protection methods have been used in adult and pediatric groups for many years. However, the immature heart in the pediatric group differs in many ways from the mature hearts in adults. Low cardiac output is more often observed in pediatric patients. Most cardiac operations are performed under cardioplegic arrest in pediatric cardiac surgery. Today there are a lot of different types of cardioplegia solutions and methods used in pediatric cardiac surgery. Soon after normothermic perfusion was used in the adult cardiac surgery in the beginning of the 1990s, normothermic perfusion and cardioplegia began to be used in pediatric myocardial protection. Myocardial protection is more challenging in particular cases such as: (i) long and complex cases in which repetitive cardioplegia administration through the aortic root is difficult; (ii) newborn patients; and (iii) cases with preoperative damaged myocardium. If the mortality and morbidity rates of the centers in complex and long procedures are higher than the reported rates in literature, the myocardial protection method must be suspected and reorganized.