Prognostic factors and treatment outcome of 71 patients with non-Hodgkin's lymphoma of Waldeyer's ring were analyzed retrospectively. In univariate analyses, unfavorable prognosis was associated with primary disease in the base of the tongue, stage III-IV diseases, B-symptoms, high-grade histology, T-cell phenotype, elevated serum LDH levels, decreased peripheral blood lymphocyte counts, and negative response on delayed type hypersensitivity skin reactions. Multivariate analysis showed that stage III-IV and T-cell phenotype were significant independent risk factors for death. In stage I-II lymphomas, patients with unilateral large or bilateral cervical lymph node involvement had a poorer prognosis. In stage I-II lymphomas with intermediate or high-grade histology, patients who had received radiotherapy with MTCOP-P chemotherapy (pirarubicin, cyclophosphamide, vincristine, methotrexate with leucovorin rescue, peplomycin, and predonisolone) showed significantly better 5-year disease-free survival rate compared with patients treated with radiotherapy alone.