Pentology of Cantrell is a complex syndrome involving the thoracic and abdominal walls, the diaphragm, and the heart. We report a case of that syndrome diagnosed early in pregnancy (16 weeks gestation) by fetal echocardiogram. The fetus had a severe form of hypoplastic right heart syndrome. Early diagnosis of such complex cardiac anatomy together with other severe anatomical malformations is important in planning the surgical intervention. It also shows the intimate relationship between the developmental anatomy and physiology of the fetal heart.