Malignant melanoma has a very poor prognosis compared to other cancers. There are no specific tumor markers other than clinical staging and depth of invasion to predict the prognosis of the malignant melanoma. The nm23 has been known to inhibit the metastasis of the malignant melanoma, some studies showed that it is highly expressed in the malignant melanoma cell line which has a relatively weak metastatic potential. In this study, we compared the expression of nm23 in mucosal type with that in cutaneous type of the malignant melanoma in the head and neck according to the stage and survival rate to identify the role of nm23 expression as a prognostic factor in mucosal melanoma of the head and neck. Six out of eight cases in mucosal type and seven out of 11 cases in cutaneous type expressed nm23, which showed no significant differences. Between the two groups there were no significant differences in expression of nm23 according to clinicopathologic staging or two year survival rate. However, in cases with low cliniopathological staging and those surviving more than two years the expression was significantly increased which suggests that expression of nm23 can be used as an aid in determining the prognosis of mucosal melanoma.