A 78-year-old man with aortic stenosis complained of dark colored urine followed by recurrent chest pain and syncopal episodes. Echocardiography showed severely calcified aortic stenosis with the maximal pressure gradient of 125 mm Hg. Hemoglobin was 7.9 g/dL, lactate dehydrogenase was 2,295 IU/L, haptoglobin was less than 10 mg/dL, reticulocyte count was elevated, and Coombs' test was negative. We performed an urgent aortic valve replacement. After the surgery, the patient's urine became clear and his chest pain and syncope abated. All laboratory data returned to normal physiological values. In conclusion, the observed hemolysis was related to the aortic shear stress of a calcified aortic valve.