Solitary abscesses of the spleen may occur as a consequence of septicemia from various septic foci, particularly intra-abdominal sites. A variety of causative organisms, including the clostridia, have been isolated. We have described a patient with multiple myeloma who had a solitary splenic abscess due to Clostridium septicum and who failed to survive despite seemingly appropriate treatment. Clinicians should be alert to this complication, which demands immediate splenectomy and appropriate antibiotic therapy.