Hemolytic anemia is one of the findings representative of prosthesis dysfunction after valve surgery. A 67-year-old man, who underwent mitral annular ring plasty one week ago, was admitted with shortness of breath and fatigue. Hematological studies revealed a Coombs'-negative hemolytic anemia with a hemoglobin 7.9 g/dl, hematocrit of 17.1%, haptoglobin of 1.0 mg/dl, LDH 5148 U/L, total bilirubin of 3.1 mg/dl (direct of 0.71 mg/dl), and a peripheral blood smear demonstrating mechanical hemolysis with red cell fragmentation. Transesophageal echocardiogram revealed a turbulent jet of mitral regurgitation hitting the annuloplasty ring. The patient returned to the operating room for mitral valve replacement, and thereafter which the hemolytic anemia resolved.