To solve the problems of selecting grinding modes based on experience and unpredictable grinding results in the current grinding operation by rail grinding trains, this paper takes the GMC-96X rail grinding train as the research object, to research the effects of different grinding modes by means of numerical simulation through MATLAB. By combining the distribution of grinding wheels in the grinding train, the basic model library of rail grinding is established, and a design method of rail grinding mode based on the grinding amount curve is proposed, which realizes the automatic generation of grinding mode and the precise repair of the rail head profile. The field test results show that the grinding mode designed by this method includes all angles of each grinding wheel of the grinding train, that can be directly input to the control system, which is more suitable for practical applications; and by comparing the measured rail profile before grinding, after theoretical grinding, and after actual grinding, the reliability of the method is verified. And this method can be combined with eddy current testing equipment to remove cracks on the surface of the rail.