A rolling bearing comprising: an inner ring having an inner ring raceway surface on an outer circumference; an outer ring having an outer ring raceway surface on an inner circumference; rolling elements that roll between the inner ring raceway surface and the outer ring raceway surface , wherein the inner ring , the outer ring , and the rolling elements are formed of iron-based material; and a hard film comprising: a foundation layer formed directly on at least one surface selected from among the inner ring raceway surface , the outer ring raceway surface , and a rolling contact surface of the rolling element and mainly formed of chromium and tungsten carbide; a mixed layer formed on the foundation layer and mainly formed of tungsten carbide and diamond-like carbon; and a surface layer formed on the mixed layer and mainly formed of diamond-like carbon, wherein: the mixed layer has a composition in which a content rate of the tungsten carbide in the mixed layer is continuously or stepwise decreased and a content rate of diamond-like carbon in the mixed layer is continuously or stepwise increased from a side of the foundation layer toward a side of the surface layer ; and in a roughness curve of a surface on which the foundation layer is formed, the arithmetical mean roughness Ra is 0.3 μm or less and characterized in that the root mean square gradient RΔq is 0.05 or less. an inner ring having an inner ring raceway surface on an outer circumference; an outer ring having an outer ring raceway surface on an inner circumference; rolling elements that roll between the inner ring raceway surface and the outer ring raceway surface , wherein the inner ring , the outer ring , and the rolling elements are formed of iron-based material; and a hard film comprising: a foundation layer formed directly on at least one surface selected from among the inner ring raceway surface , the outer ring raceway surface , and a rolling contact surface of the rolling element and mainly formed of chromium and tungsten carbide; a mixed layer formed on the foundation layer and mainly formed of tungsten carbide and diamond-like carbon; and a surface layer formed on the mixed layer and mainly formed of diamond-like carbon, wherein: the mixed layer has a composition in which a content rate of the tungsten carbide in the mixed layer is continuously or stepwise decreased and a content rate of diamond-like carbon in the mixed layer is continuously or stepwise increased from a side of the foundation layer toward a side of the surface layer ; and in a roughness curve of a surface on which the foundation layer is formed, the arithmetical mean roughness Ra is 0.3 μm or less and characterized in that the root mean square gradient RΔq is 0.05 or less. the mixed layer has a composition in which a content rate of the tungsten carbide in the mixed layer is continuously or stepwise decreased and a content rate of diamond-like carbon in the mixed layer is continuously or stepwise increased from a side of the foundation layer toward a side of the surface layer ; and in a roughness curve of a surface on which the foundation layer is formed, the arithmetical mean roughness Ra is 0.3 μm or less and characterized in that the root mean square gradient RΔq is 0.05 or less. <EOS>