In a review of nonepithelial tumors involving the nasal cavity, paranasal sinuses, and nasopharynx, 256 lesions, 156 benign and 100 malignant, were identified. Of these, 8 were smooth muscle neoplasms, 2 leiomyomas, and 6 leiomyosarcomas. The clinical findings associated with these smooth muscle tumors are described, their histologic features illustrated, results of therapy presented, and clinicopathologic correlations made. The leiomyomas were small lesions found incidentally within polypectomy specimens, and were successfully treated by polypectomy. Leiomyosarcomas could not be eradicated easily by surgery, recurred frequently, did not respond well to radiotherapy, and carried a poor prognosis.