Primary splenic lymphoma (PSL) is a rare disease. A case of PSL in which splenectomy was effective for diagnosis of lymphoma subtypes and treatment of hemophagocytic syndrome and disseminated intravascular coagulation (DIC) is presented. A 72-year-old man was admitted with symptoms of fever, general malaise, and weight loss. Imaging findings showed splenomegaly with increased FDG uptake. Although laboratory findings indicated hemophagocytic syndrome and DIC, and hematologic malignancy such as leukemia or lymphoma was suspected, core biopsies of bone marrow and skin did not confirm an obvious diagnosis. His general condition deteriorated gradually, and, therefore, splenectomy was performed for diagnosis and treatment of hemophagocytic syndrome. After surgery, his general condition and laboratory data improved promptly, and the pathological findings showed peripheral T cell lymphoma of the spleen. Splenectomy is effective for PSL in terms of not only diagnosis, but also treatment of hemophagocytic syndrome with PSL.