A 70-year-old man was referred to our department for surgical treatment for aortic valve stenosis. He was diagnosed with aortic regurgitation 30 years ago, but he was asymptomatic at that time. Ten years ago, chronic hemodialysis was instituted for diabetic nephropathy. In recent years, he became aware of nocturnal dyspnea and echocardiography revealed moderate aortic stenosis. After that, the symptom was getting worse and surgical treatment was indicated. We performed aortic valve replacement. Intraoperatively, we noticed his aortic valve was quadricuspid. The postoperative course was uneventful and he was discharged without complications. Quadricuspid aortic valve is rare congenital anomaly and patients are often operated on for aortic regurgitation. Our case is indicated for valve replacement because of aortic stenosis. In addition, there are a few reports of quadricuspid aortic valve associated with hemodialysis. We consider hemodialysis is one of the cause of rapid progression of aortic stenosis in this patient.