The invention discloses a method for compensating the positioning and distributing precision of grating scales. The method has the advantages that a plurality of preset points are arranged in the stroke of linear motors, measurement values of laser interferometers are compared to measurement values of the grating scales, linear errors and local errors of the measurement values of the grating scales can be obtained by means of comparison on the basis of the measurement values of the laser interferometers, the linear errors and the local errors of the original measurement values of the grating scales are compensated, accordingly, more accurate measurement values of the grating scales can be obtained, and the measurement precision can be improved.