Osteochondroma is the most common benign neoplasia of the skeleton. In the head it was been described in cranial base, posterior maxillary surface, maxillary sinus, and different mandibular areas like condyle, ramus, body and symphysis. Osteochondroma of the coronoid process are rare. We present a review of the literature and the report of the cas of a 44 years old female patient presenting limited mouth opening and swelling of the left cheek, with diffuse limits, bony consistency, painless, and covered of normal skin. No temporomandibular joint disease was present. In panoramic radiographs was evident a coronoid tumor localized in the union of zigomatic arch and bone. Under general anaesthesia coronoidectomy was made, recovering mouth opening until 43 mm. The post-operative period was performed without complications. Histopatological examinations revealed normal trabecular bone covered with hyaline cartilage. The histopatological diagnosis was osteochondroma. Clinical and pathological aspects, treatment and differential diagnosis with other lesions are discussed.