From October 1977 through September 1986, a total of 77 patients (Stage I, 26; II, 35; and III-IV, 16) with primary non-Hodgkin's lymphoma (NHL) of the head and neck were treated with radiation therapy and chemotherapy (CVP or CHOP regimen) or radiation therapy alone. Actuarial 5-year survival rates by stage were 79% in Stage I, 35% in II, and 8% in III-IV. Significant prognostic factors were clinical stage (p = 0.0001), histological grade by the Working Formulation (p = 0.0089), and surface marker (T and B cell analysis) (p = 0.0001). In Stage II patients, the serum lactate dehydrogenase (LDH) level (p = 0.0286), the number of cervical lymph nodes involved (p less than 0.03), and maintenance chemotherapy after initial treatment (p = 0.0077) were significant prognostic factors. In conclusion, more intensive chemoradiotherapy is necessary as the first-line treatment in those with poor prognosis, especially those with T-cell type and high grade histology. In addition, maintenance chemotherapy after initial chemoradiotherapy is very important for Stage II NHL patients, especially those with a high LDH value or multiple cervical lymph node involvement.