Malignant melanomas of the mucous membranes are rare tumors. They make up about 10% of all malignant melanomas of the head and neck; 15 of the authors' cases are reviewed in this article. Six of these had neck lymph node metastasis when first diagnosed. The tumors were surgically removed in all patients. Thirteen patients developed at least one tumor recurrence, ten patients distant metastasis. Eight patients died of the tumor condition; the mean survival time of all patients was 33.4 months. While the tumors could be classified histologically into four types, this had no bearing on the course of the disease. In many cases, primary tumor and metastasis or recurrent tumor differed histologically. Melanin pigment was found in 13 tumors. Mucosal melanomas can be regarded as a discrete tumor entity because their biological behavior differs from that of malignant melanomas of the skin. However there are no morphological differences between the two tumor entities. Ophthalmological and dermatological examinations must be performed in all patients with mucosal melanoma to exclude metastasis of the skin or choroid melanoma.