An electric motor is provided with a stator core (3) configured by laminating a required number of annular electromagnetic steel sheets (5) having a plurality of tooth portions (4) around each of which a coil winding is wound, on the inner periphery side, wherein circumferential widths (B) of the tooth portion (4) in the plurality of electromagnetic steel sheets (5) which are laminated on both end sides of the stator core (3) become gradually narrow coward the respective end portion sides, and the coil winding is directly wound around the tooth portion (4) in which shoulder portions (7) on doth sides in a circumferential direction of the tooth portion (4) which is formed by lamination of the electromagnetic steel sheets (5) are shoulder portions (7) which smoothly change so as to narrow in width in a stepwise fashion toward the respective end portions.