The invention discloses a decoloring method for recovering cutting fluids through multilineal cutting, comprising the following steps of: 1, reducing viscosity: heating coloured cutting fluids to 40-75 DEG C; 2, flocculating and decoloring: adding hydrogen peroxide, sufficiently stirring, then adding carclazyte, sufficiently stirring, and then standing so as to obtain a solid-liquid mixture with flocculates; 3, carrying out multistage filtration; 4, carrying out ion exchange processing: removing inorganic foreign ions by adopting an ion exchange column or an ion exchange bed so as to obtain defecated filter liquor with conductivity of less than 5 microseconds / centimeter under the temperature condition of 25 DEG C; and 5, carrying out negative-pressure vacuum distillation. The method has reasonable design, high practical value, good decoloring effect and low recovery cost, adopts simple step, is easy and convenient to operate, ensures that chroma of processed cutting fluids is less than 15 and various indexes all meet the requirements of technical indexes and can solve multiple practical problems of high recovery cost, unstable processed cutting fluid quality, difficult processing procedure mastering, and the like of the traditional cutting fluid recovery method.