A 43-year-old man was admitted with idiopathic fever. Abdominal ultrasonogram demonstrated multiple hypoechoic lesions in the spleen. Abdominal CT scan showed multiple hypodense lesions in the liver and spleen. The patient had a cat in his house, and the presence of a very high serous antibody titer for Bartonella henselae led to the diagnosis of hepatosplenic cat scratch disease. It is important to consider this disease in the differential diagnosis of idiopathic fever when multiple lesions are detected in the liver and spleen.