To evaluate the effects of glucocorticoids(GC) on conical bone and cancellous bone inrats with biomechanical way. Methods: Nineteen male Sprague-Dawley rats were randomly dividedinto Basal, Aging and Hormone group, the latter was given prednisone acetate (4.5mg/kg) twice aweek. The torsion, three-point bending and compression tests were respectively made on femurs and3ird--5th lumbar vertebrae of three groups after 3 months. Results: In GC group, the loads imposedon the femoral middle segments in three-point bending and on the lumbar vertebral(no-vertebralarch) in compression tests were separately decreased by 17.1 %(p<0.05) and 29.9%(p<0.05) thoughthe rest parameters tended to decrease, compared with the control group. Conclusions When GCused for a long time, the biomechanical characters of conical and cancellous bone in the rats wouldbe led to decrease and bone fracture be prone to occur.