By testing the physical and chemincal properties of various tundish slide plates and tracking the service lifes of different slide plates in high oxygen steel,the micro structures and XRD patters of the residual zirconium oxide ring bricks in two tundish slide plates were analized.By comparing the physical and chemical properties of the test bricks with the original brick,the cause of abnormal failure of the zirconium oxide ring slide plate was studied and the damage mechanism was analyzed.