Abstract: The perforated completion is by far the most popular method of completing a well at home and abroad.But lots of field applications indicate that perforation has serious effect on the casing safety,how to guarantee the collapse strength of perforating casing is still a difficult subject to the development of the petroleum industry.In this paper,the spacial finite element mechanics model of the strength analysis of perforating casing with screw holding was established by using non-linear elasticity-plasticity finite element method.In the model the parameters including perforation diameter,perforation density,perforation phase angle,wall thickness,casing dimension and material mechanics property of casing with different steel rating can be changed discretionarily,so the finite element analyses on synthetic factors of perforating casing’s collapse strength can be carried through conveniently.Detailed analyzing the change of collapse strength and remaining strength on the casing with different steel rating,wall thickness,and dimension under outer loading,the result of the investigation provides a theoretical basis for rational choosing casing and prolonging their life.