Introduction: Belonging to the group of Giant and Cystic Cell Lesions of the 4th Edition of the Head and Neck Tumours Classification by WHO, the Central Giant Cell Granuloma is an intraosseous osteolytic lesion, with and unknown etiology, characterized by a benign proliferation of fibroblasts and osteoclast-like giant cells, within a well vascularized stroma. Most of these lesions happen in the anterior sector of the maxillary bones, in women under 30 years of age, being typically assimptomatic and non aggressive. The conventional therapy for the Central Giant Cell Granuloma is the surgical complete enucleation. Clinical Case: Femmale caucasion patient, 21 years old, sent by her medical assistant for evaluation of a radiolucent lesion in the posterior mandible, between teeth 47 and 48. A CBCT was required and after that, the tooth 48 was extracted and an access to the lesion was created followed by it's enucleation and anatomopathological analysis. The analysis result sugested the diagnosis of a Central Giant Cell Granuloma (CGCG), asking for a differentiation between the four entities, due to both having the same morphological pattern. The distinction and exclusion of these entities was based on three criteria: Radiological (Cherubism), Blood Tests (Hyperparathiroidism) and Histological (Aneurismatical Bone Cyst), concluding in this was, the diagnosis of CGCG. Discussion: Some of the caracteristics found in this case are typical of a CGCG, like the gender, age and lack of symptoms envolved. However, the location of the lesion does not follow the normal patterns of a CGCG, once it envolves the posterior mandible, and being so, this entitie was not suggested as a diagnostic hypothesis. The definit diagnosis was then established by the anatomopathological analysis. For the treatment of the lesion, total enucleation was made, as it is established by the literature as the therapy to follow. Conclusion: Although typically not aggressive, the Central Giant Cell Granuloma may appear with a destructive and painfull character, and can be similar, either radiographically or histologically, to other conditions that are more aggressive or have a systemic envolvnment, making the early diagnostic and intervention of extreme importance. Schlagwörter: Central Giant Cell Granuloma, Oral Pathology, Osteolytic Lesions, Head and Neck Tumours