Until now 19 patients were treated for osteoblastoma in our University Department. Operation was performed in every case and recurrence was found in one patient. The clinical-pathological characteristics of the benign, latent, active and aggressive osteoblastomas are discussed. In benign active process excision, in benign aggressive tumors, depending from the localization, resection en bloc is suggested. In cases localized near to the joint, weighing the damage of function in consequence of a possible resection and the increased risk too, a thorough excision is proposed completed with local adjuvant treatment and frequent control of the patient.