Plain roentgenography of congenital heart disease in newborn is subject to narrow diagnostic limitations. The cardiac abnormalities should preferably be classified according to haemodynamic criteria. In most cases the diagnostic information is restricted to the statement whether the malformation detected plain roentgenography is associated with normal, increased or decreased pulmonary perfusion. Most cardiac abnormalities occur in conjunction with a more or less pronounced cardiomegaly, and only the tetralogy of Fallot, tricuspid atresia, and total anomalous pulmonary venous drainage are associated with a heart of normal or only slightly enlarged size. Configurations which are considered as being typical of congenital heart disease are only seen in the tetralogy of Fallot and in tricuspid atresia (wooden shoe deformity) on the one hand, and in the transposition of the great arteries and the truncus arteriosus on the other eggshaped heart). Differentiation between these malformations of the heart is sometimes possible via the position of the aortic arch. The factors mainly responsible for the development of cardiac insufficiency during the first few days of life should be the coarctation of the aorta and the hypoplastic left-heart syndrome.