Osteosarcoma (OS) is one of the most common primary malignant bone neoplasms, which predominantly occurs in the long bones and rarely in the maxillofacial area. We present a rare case of maxillary OS early diagnosed in a 17-year-old girl through clinical, radiological and histological examination. The treatment involved surgical resection of the tumor followed by radiation therapy and chemotherapy. The patient was much younger than the average age of presentation of a jaw tumor, which typically presents in the third to fourth decades of life. Although there is a consensus in the literature that OS of the jaws is less aggressive and less prone to metastasis than OS of the long bones, that was not true in this case, where in spite of early diagnosis and treatment the patient died due to brain metastasis.