The authors report a rare association between cutaneous melanoma and Von Recklinghausen's disease (NF-1) and analyze the possible meaning of this occurrence. Various types of tumors have been associated with NF-1, in particular those of neuroectodermal origin, such as malignant peripheral nerve sheath tumors (MPNST) and phaeochromocytoma. The development of malignant melanoma in NF-1 patients is rare. Data from the literature is enable to demonstrate an increased incidence of cutaneous melanoma in patients with neurofibromatosis but the association of these two disorders seems reasonable in theory, as both are abnormalities of a neural crest origin. The cases described may represent not only a clinical report of two rarely associated disorders, but may also confirm the biological mechanisms responsible for these infrequent diseases.