A 47-year-old woman was admitted to our hospital with high fever, exertional dyspnea and left flank pain. Echocardiography revealed vegetations attached to the aortic valve and moderate aortic regurgitation. Streptococcus anginosus was identified by blood culture examination. Abdominal CT scan showed a low density area in the spleen. The diagnosis of infective aortic valve endocarditis with splenic abscess was obtained. The splenectomy and the aortic valve replacement were performed simultaneously after the treatment with antibiotics. The postoperative clinical course was uneventful. In the case of infective endocarditis with splenic abscess, the splenectomy concomitant with valve surgery should be performed for removing all of the infected tissues.