The case of an intraosseous leiomyoma in a 22-year-old man is presented. The tumor was incidentally discovered during dental radiographic examination for endodontic treatment of mandibular first molar. Radiographic examination revealed a well-defined unilocular radiolucency between the roots of mandibular left canine-first premolar, measuring approximately 1.9 x 1.8 cm and perforation of the buccal cortical plate. Histological and immunohistochemical examination was diagnostic of intraosseous solid leiomyoma. Here, we report a rare case of leiomyoma of the mandible, together with conventional histopathologic and immunohistochemical findings.