Disclosed is a method of manufacturing a core sheet. The core sheet has an annular core back portion and a plurality of tooth portions extending from the core back portion toward a radial center thereof. The method includes a blanking step, a rolling step and a removing step. In the removing step, an insulation coating, which is on a region of a grain-oriented magnetic steel sheet for forming a band-shaped core back portion, on a band-shaped core back portion of a sheet piece or on the core back portion of the core sheet, is at least partially removed.