The invention relates to a method for separating and purifying 1,1,2,2-tetrafluoroethyl-2',2',3',3'-tetrafluoropropyl ether through extractive distillation with salt. The method specifically comprisesthat tetrafluoropropanol and a tetrafluoroethylene monomer are subjected to a nucleophilic addition reaction under the catalysis of an alkali by using deionized water as a protic solvent to prepare the crude reaction liquid of 1,1,2,2-tetrafluoroethyl-2',2',3',3'-tetrafluoropropyl ether, the organic phase obtained from the lower layer of the crude reaction liquid is subjected to water washing anddistilling to obtain a crude product, and the crude is further purified through extractive distillation with salt, wherein the content of the target product can be greater than or equal to 99.0%, thepure product can be obtained, and the average yield is 80-85%. According to the present invention, the detection results show that the water content is less than 500ppm so as to meet the use requirements of the relevant industry on fluorine-containing cleaning agents.