Osteoblastoma is rare that a primary tumor is approximately 1% of all primary bone tumors. Its occurrence in the region cranial-maxillo-facial surgery is rare and represents only 15% of all osteoblastoma. The tumor has a predilection for males and is less than 1% of all tumors of the maxillofacial region. In these cases, the mandible is affected more frequently than the maxilla. The presence of osteoblastoma in the ethmoid sinus is very rare and only few cases have been described. OBJECTIVE: We report a case of osteoblastoma of the ethmoid sinus between the fixed orbit, floor of anterior tank and the middle turbinate. Methods: Female patient, 35 years old, was diagnosed with bone density tumor in the ethmoid sinus with fixing the lamina papyraceous and the floor of the anterior tank, underwent surgical resection by endoscopic technique centripetal. RESULTS: There was complete tumor resection without complications and postoperative trans. CONCLUSION: The endoscopic surgical technique centripetal proved effective and safe for the resection of osteoblastoma of the ethmoid sinus.