Congenital ventricular septal aneurysm without ventricular septal defect is a very rare condition. We describe the clinical features of an adult case and the literature was reviewed. A 54-year-old woman experienced intermittent palpitation with rapid heart beating sensation for several years. The duration was only several seconds. There was neither congestive heart failure nor syncope history. Physical examination revealed mid-systolic click with grade II/VI systolic murmur at apical area. Echocardiography disclosed mitral valve prolapse with mild mitral regurgitation. A ventricular septal aneurysm bulging into right ventricle was found incidentally. Transesophageal echocardiographic and cardiac angiographic pictures of ventricular septal aneurysm were demonstrated. Since the patient was relatively asymptomatic, no surgical intervention was advised.