PURPOSE: A review of the literature for patients with peripheral primitive neuroectodermal tumor (PPNET; peripheral neuroepithelioma) suggests that the outcome is usually poor. We performed a retrospective study to emphasize the need for triple combined therapy of PPNET. METHODS: The clinical data of 10 patients (M:F=1:1, aged 1 8/12~14 3/12 years) with PPNET seen at Seoul National University Children's Hospital from Jan. 1991 to Jun. 1998 were reviewed. RESULTS: The primary sites were head and neck, chest, limbs, and retroperitoneal area in order of frequency. A palpable mass was the major symptom. The median duration of symptoms before diagnosis was 3 months. Metastatic disease at diagnosis was found in 3 patients, 2 of them were multiple. All of the patients had combined modality treatment with surgery, chemotherapy and radiation therapy. The 3-year relapse-free survival rate was 64%, and the overall 5-year survival rate was 66%. CONCLUSION: Best results were obtained with combined therapy with combination chemotherapy, extensive surgery and local radiation therapy.