Deformability　is　very　important　for　pipelines　working　in　harsh　geology　areas　where　earthquake　or　land　slid　always　occur,　in　that　conditions　pipelines　will　sustain　large　displacement　and　strain　based　design　is　suitable.　Deformability　of　two　type　high　grade　line　pipes　(X70-1,　X70-2,　X80-1,　X80-2)　was　studied　with　finite　element　method　(FEM),　4　nodes　shell　element　was　used　in　analysis.　The　results　show　that　pipe　will　buckle　in　symmetry　mode　near　the　two　ends　of　pipe　under　compression　load.　In　the　local　buckled　area,　wrinkles　will　form;　stress　and　strain　will　concentrate.　The　pipes　of　X70-2　and　X80-2　with　lower　yield　ratio,　higher　strain　hardening　exponent　and　higher　uniform　elongation,　show　higher　buckling　strain,　higher　limit　strain　and　higher　deformability.　So　the　effective　ways　to　improve　the　deformability　of　line　pipes　are　to　decrease　yield　ratio,　increase　strain　hardening　exponent　or　uniform　elongation.