An unusual case of cardiac rhabdomyomatosis associated with a ventricular septal defect without signs of tuberous sclerosis is described. On 3 different angiocardiographies the region of the tumor seemed to be a right ventricular aneurysm. The tumor was identified as such only on operation and its nature defined histologically. Subtotal excision of the tumor and closure of the large ventriccular septal defect and debanding (pulmonary banding at the age of 8 month) was successfully undertaken at the age of 10 years.