Ewing sarcoma is a rare tumor in head and neck area. We demonstrate a rare case of sinonasal Ewing sarcoma initially suspected as olfactory neuroblastoma. After the surgery and immunohistochemical studies, it was accurately diagnosed as Ewing sarcoma. We would like to emphasize the possibility that Ewing sarcoma may originate from the head and neck area, and hence, it is important to use appropriate techniques for accurate diagnosis and treatment.