Mucoepidermoid carcinoma is a common salivary gland tumor. It comprised 8% of all salivary gland tumor and originated mainly in parotid gland. Central mucoepidermoid carcinoma is rare. It comprised $2{sim}3%$ of all mucoepidermoid carcinoma, but it occurs in the mandible two or three times more frequently than in the maxilla. Central Mucoepidermoid carcinoma are frequently associated with an odontogenic cyst, such as dentigerous cyst, in which mucous goblet cell would have neoplastic transformation. In May 2002, a 25 year-old male visits in our clinic, presented with a progressive facial swelling after surgical tooth extraction of left mandibular third molar at 1999 in the army. After incisional biopsy, the lesion was confirmed as mucoepidermoid carcinoma so we performed tumor resection and reconstruction surgery of mandible.