Myocardial noncompaction is an extremely uncommon cardiomyopathy. It can present as an isolated cardiac malformation or in association with other congenital anomalies. The left ventricle is usually affected, but a biventricular involvement rarely occurs. A predominant right ventricular involvement has not been reported. Here, we report an 18-year-old woman with biventricular noncompaction that predominantly involves the right ventricle.