Leiomyosarcoma(LMS) is a malignant neoplasm of smooth muscle origin, which accounts for 7 % of all soft tissue sarcomas. The most common sites are the gastrointestinal tract and female genital tract. In contrast, primary LMS of the oral and maxillofacial area is rare due to the paucity of smooth muscle in this region. Especially, LMS of the paranasal sinuses is very rare and has an aggressive clinical behavior. Only 28 cases have been described in the english literature, and of these, only 3 patients treated with surgery had a disease-free survival. A 46-year-old woman came to our department for the evaluation of pain on right midface. After a diagnostic work-up, the lesion was diagnosed as LMS of the right maxillary sinus. The radical surgery was done and chemotherapy combined radiotherapy was followed from post operation 1 month. The patient was disease free at post-operation 1 year. We will report this case with literature review.