Abstract: Due to many factors such as long term injection de- velopment,frequent measure treatment,well body struc- ture,quality of well completion and well cementing,sub- stance capability of casing,corrosion,etc,the speed of casing failure presents the regularity of ascending line.On the basis of sufficient spot field investigation,all kinds of types of casing failure have been systemically studied,its failure factors and forming mechanism are analyzed,and finally the suggestions and measures to prevent or de- crease the casing failure in oilfield development are provid- ed.