Objective: The nm23 gene is one of the tumor metastatic suppressor genes. The expression of nm23-H1 has been reported to be inversely associated with metastatic potentiality in a number of human carcinomas,including breast, colorectal, gastric, hepatocellular and gallbladder carcinomas. In this study, the immunohistochemical staining of nm23-H1 protein in human nasopharyngeal carcinoma (NPC) was examined, and the relationship between nm23-H1 and both metastasis and prognosis of patients with NPC was also investigated.Methods: Routine LSAB immunohistochemistry with the nm23-H1 monoclonal murine antibody was employed to study the expression of nm23-H1 protein in 95 paraffinembedded specimens of NPC treated at our hospital.The clinical pathologic data and results of follow-up were also retrieved. Comparisons between patients with and without expression of nm23-H1 protein with respect to metastasis, Ioco-regional recurrence and survival were performed using Log rank test. Multivariate prognostic analyses were performed by using Cox’s regression model.Results: Nm23-H1 negative expressive tumors were associated with a higher incidence of lymph-node metastasis(86.7%) than those of nm23-H1 positive (48.6%, P＜0.01).Nm23-H1 negative expressive tumors were associated with a high incidence of recurrence and distant metastasis after radiotherapy (P＜0.05). A significant association was found between expression of nm23-H1 and prognosis(P＜0.01). The expression of nm23-H1 indicated favorable prognosis. Conclusion: It was suggested that nm23-H1 negative expression was significantly associated with lymph-node metastasis, recurrence and distant metastasis.Nm23-H1 may have value for predicting the prognosis of NPC.