Malignant melanoma comprises 1.2% of all malignant tumors and more than 90% of malignant melanoma arises in the skin. About 0.5% to 0.85% of all malignant melanomas occur in the nasal cavity. Malignant melanoma developing in the oral cavity is extremely rare. The authors experienced one case originated from the nasal cavity and another from the oral cavity diagnosed as malignant melanoma. We reviewed the literatures related to the malignancy and report these two cases.