PURPOSE To study the clinical features and outcome for primary non-Hodgkin's lymphomas of the nose/nasopharynx (NNP-NHLs) according to immunophenotype. PATIENTS AND METHODS One hundred thirteen Chinese patients with primary NNP-NHLs that belonged to the categories E, F, G, or H according to the Working Formulation (WF), with full immunophenotypic data and complete clinical follow-up data, were analyzed in this retrospective study. RESULTS Ninety (79.6%) patients had localized (stage I or II) disease, while 23 (20.4%) had stage III or IV disease. The lymphomas in 51 (45.1%), 24 (21.3%), and 38 (33.6%) patients showed natural killer (NK)/T- (CD56-positive), T-cell, and B-cell immunophenotype, respectively. Seventy-three patients (65.8%) achieved a complete remission, of whom 34 (46.6%) subsequently relapsed. The median follow-up time for those alive was 88 months. The 5-year actuarial disease-free and overall survival rates were 34.4% and 37.9%, respectively. Multivariate analysis showed that only stage and immunophenotype were significant for survival. NK/T lymphomas were distinctive among the three immunophenotypes in the following aspects: the highest male-to-female ratio, more frequent involvement of the nasal cavity alone, higher risk of dissemination to the skin, more frequent development of hemophagocytic syndrome, and the worst prognosis (overall median survival, 12.5 months). CONCLUSION The three immunophenotypes studied are shown to exhibit different clinical patterns. Since the NK/T phenotype carries the worst prognosis, patients who present with NNP-NHL should have their tumors analyzed for CD56 expression.