The present invention has as its technical problem the provision of a clad steel sheet having a top layer with an average micro-Vickers hardness of 400HV or more while being excellent in bending resistance. The steel sheet of the present invention is steel sheet including an inner layer and a hard layer formed on one or both surfaces of the inner layer, wherein a content of C in the hard layer is more than a content of C in the inner layer and a content of Mn in the hard layer is more than a content of Mn in the inner layer, a thickness of the hard layer is 20 µm or more and a total of the thickness of the hard layer is 2/5 or less of the entire sheet thickness, an average micro-Vickers hardness of the hard layer is 400HV or more and less than 800HV, an average micro-Vickers hardness of the inner layer is 350HV or more and is 50HV or more smaller than a hardness of the hard layer, and a screw dislocation density of the inner layer is 2.0×10 13 m/m 3 or more.