Calcifying epithelial odontogenic tumor (CEOT), Pindborg tumor, is a rare benign odontogenic neoplasm representing about 0.4-3% of all odontogenic tumors. This tumor more frequently affects adults in an age range of 20-60 years, with a peak of incidence between 40 and 60 years. About 190 cases of CEOT have been reported in the dental literature. Fifty-two percent of cases of CEOT is associated with a tooth impacted and/or displaced by the tumor. The primary CEOT has a recurrence rate of 10-15%, after total excision, and its malignant transformation is a very rare occurrence. The authors report a case of primary intra-osseous CEOT, embedding the mandibular right second molar, in a 24 year-old male. Radiographs showed a well-defined unilocular osteolytic lesion, swelling and reabsorbing the mandible and displacing the inferior alveolar nerve. It was possible to perform conservative surgical treatment consisting of the enucleation of the tumor together with a portion of tumor-free bone cavity margin and the debridement of the inferior alveolar neuro-vascular bundle, which was surrounded by a tumor capsule-like structure. The postoperative histological examination of the tumor revealed typical benign features. The differential diagnosis and work-up of the tumor treatment are discussed in relation with its histological typing and localization in the jaws.