To reduce deformation of a steel member of a rolling bearing, which is brought into contact with a steel ball or a roller to support a load, and achieve high hardness.

In a curing method, a steel member of a rolling bearing has a carbon content of 0.3-0.45% and a chromium content of 1% or more, is subjected to annealing and tempering to have a hardness of HRC 40-50 as a whole, is molded by cutting work and subjected to nitridation to have a surface layer with high hardness, and thereby a precise hardness distribution without excess and shortage is formed in a state of less deformation so that the steel member can resist against a shearing stress caused in the entire region from the surface layer to a deep part due to a load applied on the steel member during use.