A laminated core has a plurality of steel plates that are laminated in a thickness direction. The laminated core has a line shaped welding mark connecting a plurality of steel plates. The welding mark extends over the plurality of steel plates at the end face where the plurality of steel plates are exposed. The welding mark has a welding depth which fluctuates with a wavelength that is longer than the thickness of the steel sheet. The welding mark has a continuous portion in which the welding depth extends over a plurality of steel plates without fluctuation. Furthermore, the welding mark has a fluctuation portion in which the welding depth periodically fluctuates over a plurality of steel plates. The depth in the continuous portion is substantially equal to the depth in the fluctuation portion.