Primary malignant melanoma of the mucosa of the nasal and paranasal sinuses is rare, difficult to treat, and usually has a poor prognosis. Seven cases, six women and one man (mean age 76.5 years), were treated at the Hospital 12 de Octubre (Madrid, Spain) during the period 1982-1994. The presenting symptoms, diagnostic evaluation, morphology, therapeutic modalities, histological evaluation, and clinical course were reviewed. Three patients were treated surgically and three received palliative irradiation. All had local recurrence or distant metasfases within 15 months after concluding treatment. The seventh patient refused treatment.