in a rolling bearing having a rolling bearing ring and a rolling element of at least 20 mm in diameter , at least one of the rolling bearing ring and the rolling element consists of carburized or carbonitrided steel containing at least 0 . 2 wt % and not more than 0 . 35 wt % of carbon and at least 2 . 2 wt % and not more than 3 . 6 wt % of ni . thus obtained is a rolling bearing capable of reducing the material cost and increasing the fatigue life or reducing the carburizing time by ensuring surface hardness and optimizing the case depth .