The invention provides a reversible deformation correcting method for an elliptical gear ring subjected to deformation after carburization, which comprises the following steps of: measuring the addendum circle diameters of a gear ring which is subjected to 
ellipse deformation after carburization every 30 degrees, wherein the difference between the measured addendum circle diameters is the major axis and the 
minor axis of the gear ring which is subjected to 
ellipse deformation; binding a layer of heat insulation cotton at both sides of the inner end surface of the gear ring in the 
minor axis-distributed area with iron wires at a moderate tightening degree; and exposing other gear rings and external gear parts. In the 
quenching process, the elliptical gear ring is heated to 810 DEG C at a heating rate of 60 DEG C / h and is kept for 4 hours. Because the 
minor axis-distributed area is covered with the heat insulation cotton, the heating rate of the minor axis-distributed area covered with the heat insulation cotton is smaller than that of the major axis-distributed area uncovered with the heat insulation cotton, and the 
cooling speed of the minor axis-distributed area of the gear ring is smaller than that of the major axis-distributed area in the 
quenching oil cooling process, thereby correspondingly reducing the difference between the distributed areas with different addendum circle diameters of the gear ring and consequently realizing the reversible deformation correction of the elliptical gear ring.