Myocardial noncompaction is a rare type of cardiomyopathy which can be an isolated entity or in association with other congenital heart diseases. We present three children with myocardial noncompaction: one male with isolated left ventricular noncompaction, another with right ventricular noncompaction and dysplastic tricuspid valve, and the last with left ventricular noncompaction, ventricular septal defect and coarctation of aorta, to stress especially the different clinical forms of the disorder and the importance of early diagnosis, as it may result in a fatal outcome.