A clinico-pathologic and immunohistochemical study of 20 cases of primary non-Hodgkin's lymphoma on the parotid gland was made.The result showed 45% of the cases originated from B cells,white 40% from T cells,the rest 15% from the small lymphocytes.Immunohistochemical study was made on 11 cases,the result of immunophenotype was in concordance with the histopathologic diagnosis in 10 cases,except in one case which was initially diagnosed as plasmocytoid lymphocytic lymphoma,but the immunmophenotype suggested that it was T cell type of malignant lymphoma(ML).Follow-up data can be collected in 16 cases(80%).Three of the 16 cases(18.75%) died of the tumor within one year,they were diagnosed initially as B cleaved cell,lymphoplastic cell and polymorphic T cell type of ML,each in 1 case.Other cases survived from 15 months to 9.25 years,among them 2 were diagnosed as low-grade ML(both of small lymphocyte type),7 cases as middle-grade ML(5 of B cleaved cell,2 of B mixed type),and 4 cases as high-grade ML (2 of clear T cell,2 of polymorphic T cell type).They were treated by surgical removal and combined western and traditional Chinese medicine,their prognosis was quite good.