The invention discloses a method for rapidly identifying and non-destructively repairing high-speed rail subgrade frost boiling diseases. Ground penetrating radar and a wave velocity reflection deviceare adopted for detecting high-speed rail subgrade so as to obtain disease areas, grouting holes are formed in the disease areas, and a modified polyurethane material is injected into the disease areas through the grouting holes, the ground penetrating radar and a conical dynamic sounding device are used for detecting the disease areas, and the grouting holes in the disease areas meeting the detection requirements are sealed. The method has the advantages that the disease detection efficiency is high, filling and reinforcing are conducted aiming at the high-speed rail subgrade, the construction efficiency is high, the material consumption is controllable, material waste is reduced, and the material filling effect is good.