To determine the biologic behavior, risk factors for recurrence, and influence of multimodality therapy on outcome for children and adults with rhabdomyosarcoma of the nose and paranasal sinuses. Retrospective review of medical records. During a 36-year period 37 patients (median age, 23.0 years) with histologically confirmed rhabdomyosarcoma of the nose and paranasal sinuses were treated for cure. Median follow-up was 28 months (range, 1 to 260 months). Histologic subtypes included embryonal, 16; alveolar, 15; mixed, 1; and unclassified, 5. Cervical metastases were present in 38%. Patients were treated with surgery, 4; radiotherapy, 3; chemotherapy, 3; surgery and radiotherapy, 1; surgery and chemotherapy, 1; chemotherapy and radiotherapy, 24; and chemotherapy, radiotherapy, and surgery, 1. The overall 5-year survival was 44%. For patients treated with chemotherapy and radiotherapy or chemotherapy, radiotherapy, and surgery, the 5-year survival was 60%, compared with 19% for patients treated with the other forms of therapy. Factors associated with poorer survival were adult onset of disease, alveolar histology, and treatment with systemic chemotherapy for less than 1 year. Patients receiving chemotherapy for greater than 1 year had a 5-year survival of 82%, compared with 71% for those with less than 1 year of treatment. Improved survival was associated with a lower incidence of distant metastasis. A combination of chemotherapy and radiotherapy may provide the best means of obtaining local-regional control for rhabdomyosarcoma arising in the nose and paranasal sinuses. The risk of regional disease is high, requiring comprehensive radiotherapy to the neck in addition to the primary site. Surgical resection should be reserved for patients with residual disease after chemotherapy and radiotherapy. Administration of chemotherapy for more than 1 year is associated with improved survival because of a decreased incidence of metastatic disease.