An 81-year-old man with a 1 year history of Sjögren's syndrome and hypergammaglobulinemic purpura was admitted because of high fever and lymphadenopathy. Primary nodal plasmacytoma was suggested from the microscopic and immunohistochemical findings of an inguinal lymph node biopsy specimen. Although chemotherapy achieved a moderate response, the patient died 2 months later from respiratory and cardiac failure. We herein, is described a rare autopsy case of primary nodal plasmacytoma associated with Sjögren's syndrome, in which the clinical course was progressive and Epstein-Barr virus-encoded RNA 1 was positive in a small number of neoplastic plasma cells, showing some difference from previously reported cases.