Optimal management of patients with localized Waldeyer's ring (WR) lymphoma remains controversial due to the lack of randomized studies and heterogenous grouping of most reported series. In this retrospective study, we have evaluated the possible prognostic factors and treatment outcome of WR non-Hodgkin's lymphoma. Between December 1993 and February 2000, 32 patients with WR lymphoma, stage I (11 patients) and stage II (21 patients) were treated. There were 17 male patients and 15 female patients with a median age of 47 years. The distribution among different anatomical sites were as follows: tonsils in 16 (50%), nasopharynx in 10 (31%), base of tongue in 6 (19%). According to Working Formulation, 10 had high-grade, 17 intermediate grade, 3 low-grade, and 2 bad unclassified lymphomas. Combined chemotherapy and radiotherapy was the primary modality of therapy for intermediate or high-grade lymphoma. Radiotherapy alone was employed only in low-grade WR lymphomas. Chemotherapy was median 6 courses of CHOP (cyclophosphamide, doxorubicin (Adriamycin), vincristine, and prednisolone) in 26 patients and CEOP (cyclophosphamide, doxorubicin, etoposide, and prednisone). Radiotherapy volume was involved field and the median dose was 40 Gy. Median follow-up is 40 months (ranged from 6-82 months). Overall survival and disease-free survival (DFS) rates at 3 years are 100% and 92%, respectively. Two patients developed recurrence, both salvaged with further chemotherapy. Only one patient died because of other reasons. International Prognostic Index score (less than or equal to2 vs. >2) is found to be an important prognostic factor for DFS. The other significant prognostic factors for DFS are performance status and serum levels of alkaline phosphatase and lactate dehydrogenase. Our results suggest that combined chemotherapy and involved field radiotherapy is appropriate treatment for stage I-II WR lymphoma. International Prognostic Index is the strongest predictor for DFS.