We report one case of Non Hodgkin's Lymphoma which was classified as Histiocyte Rich B cell lymphoma on immunocytochemistry. The diagnosis was difficult on fine needle aspiration cytology and routine histopathological examination as the infiltrate was composed of reactive lymphocytes and numerous histiocytes obscuring the lymphoma cell population. The neoplastic cells were positive for CD20(L26-A Pan B marker) and negative for CD15(Leu M1), CD3(Ber H2) and pan T cell markers. The histiocytes were positive for CD3(UCHL-1). The patient had a rapid downhill course and died. The autopsy showed infiltration in the axillary, cervical, mesenteric, para aortic, peri pancreatic and hilar lymph nodes. The liver, spleen, bone marrow and kidney also showed lymphomatous infiltration.