To solve a problem wherein a value itself of compressive residual stress of a generated surface layer is low, and fatigue strength is not sufficient since hardness of a shot grain is low or a grain size of the shot grain is large in a conventional shot peening.

In this shot peening method to be performed after performing carburizing treatment for a surface of a steel member, first shot peening is performed by the first shot grain having hardness ≥HRC60 in Rockwell hardness and the grain size ≥200μm and ≤400μm, and second shot peening is performed by the small second shot grain having hardness ≥HRC60 in Rockwell hardness and a grain size ratio ≥0.1 and ≤0.3 to the first shot grain. More preferably, both of the hardness of the first shot grain and the second shot grain are made ≤HRC65 in Rockwell hardness.

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