We have experienced two elder patients with Atrial Septal Defect (ASD) over the age of 70. The first case was a 72 years old woman. She was diagnosed as valvular disease several years ago. Recently she suffered from epigastralgia and came our hospital for examinations of her gastrointestinal tract. A gastrointestinal fiber scope revealed that she suffered from malignant lymphoma of the stomach. The echocardiogram was done to estimate her valvular disease, but she was diagnosed as ASD. A total gastrectomy was done without complications. She recovered well, and was discharged without any cardiac symptom. The second case was a 74 years old woman. She was admitted to our hospital because of dyspnea, appetite loss and nausea. She was diagnosed as valvular disease several years ago. Further examinations revealed that she suffered from ASD and digitalis toxication. The digitalis was withdrawn, and she was treated with diuretics. She successfully recovered and was discharged. We strongly emphasize that we should never forget to check for congenital heart disease on hearing heart murmur, regardless of the age of the patients.