Research conclusions: ( 1) With small amounts of transformation and optimization for CTCS － 2 system，the CTCS － 2 can meet the transport demand of inter － city railway． The scheme of using CTCS － 2 in inter － city railway is feasible． ( 2) The optimum proposal of CTCS － 2: When CTCS － 2 is used in inter － city railway ，due to short distance between stations and great engineering investment，the author proposes a scheme that adjacent stations can share a set of interlocking and Train Control Center ( TCC ) equipment． And this way can reduce the engineering investment effectively． ( 3) Technical upgrading proposal: The wayside and onboard equipment of CTCS － 2 can be reformed properly by increasing onboard ATO units and a small number of balise to achieve the ATO － related function．