Small cell neuroendocrine carcinoma of the sinonasal tract is a rare disease. Five cases of sinonasal small cell neuroendocrine carcinoma were treated between 1991 and 2005 in National Cheng Kung University Hospital. Three of the patients were male and two were female, with a mean age at presentation of 54 years (range: 21 to 77 years). Surgery was the primary treatment except one patient. After surgery, two patients received post-operative concurrent chemoradiotherapy and the others received postoperative radiotherapy. Loco-regional recurrence or distant metastasis occurred in 4 cases during one year after treatment. One patient was alive with a local recurrence at a follow-up period of 112 months after combined modality treatment. Sinonasal small cell carcinoma is an uncommon neoplasm with aggressive clinical behavior. Recurrence is frequent and the prognosis is poor. Combined chemotherapy, radiotherapy and surgery is advocated.