Inflammatory pseudotumor is a benign disease, which is histologically composed of the inflammatory cells such as mature lymphocytes, plasma cells, and histiocytes. It usually occurs in the respiratory system, liver, central nervous system, and gastrointestinal tracts. However, inflammatory pseudotumor rarely occurs in the spleen. Pathologic diagnosis is essential for the definitive diagnosis because of the difficulty in distinguishing pseudotumor from lymphoproliferative disorders of the spleen. We report a case of inflammatory pseudotumor of the spleen. A 35-year-old woman complained of the intermittent epigastric pain for several months. Physical examination and laboratory findings were normal. Ultrasonography and abdominal computerized tomography showed a low attenuation splenic mass suggesting lymphoma. However, the pathologic findings of the resected spleen were consistent with those of the inflammatory pseudotumor. The spleen weighed 230 g containing a 6 X 5 X 5 cm-sized, well-circumscribed gray mass. The microscopic findings indicated the inflammatory cell infiltrations.