Osteosarcoma(OS) is the most common primary tumor of bone, with a low incidence. osteosarcoma comprises a family of lesions with  diverse in histologic features and grade. Its prognosis is dependent on the histology and prognostic parameters. It may occur inside the bones (in the intramedullary or intracortical compartment), on the bone surface and  extraosseous sites.OS occurs in a varied age group and with different radiological features . This review summarizes the anatomic,clinical and histologic variations of osteosarcoma.