Aseptic abscess (AA) is characterized by accumulation of neutrophils without evidence of infection, no response to antibiotics, and rapid response to corticosteroids. We report a case of multiple abscesses in the subcutaneous tissues and joints, and severe mitral valve regurgitation. Although AA did not respond to antibiotic therapy, it improved dramatically with corticosteroid treatment. However, repeated valvuloplasty was required for the mitral valve regurgitation. The mitral valve tissue showed neutrophil infiltration without any bacterial invasion. This is the first case of AA to show involvement of cardiac valves, indicating the importance of systematic examination for patients with AA and cardiac valve involvement.