A squirrel-cage induction rotating electrical machine comprising: a solid rotor extending axially and supported rotatably, including a shaft part and a columnar-shaped rotor core part integrally formed with the shaft part, the columnar-shaped rotor core part having a diameter larger than that of the shaft part and having rotor slots formed therein which are disposed with circumferential intervals therebetween and extend axially, and a plurality of conductor bars passing through the respective rotor slots and coupled together at both axial ends outside the rotor core part; a stator having a cylindrical stator core provided radially outside the rotor core part and stator windings passing through a plurality of respective stator slots which are formed in the radially inner surface of the stator core so as to be disposed with circumferential intervals therebetween and to extend axially; and two bearings supporting the solid rotor at both axial sides of the shaft part, sandwiching the rotor core part, wherein a virtual plane positioned at a center between two opposing and parallel to each other walls (14a, 14b) of each rotor slot is tilted at a predetermined angle with respect to a plane passing a rotation center axis of the solid rotor, and a radial outer end portion of each of the plurality of conductor bars is flush with the radially outer surface of the rotor core part forming a cylindrical shape, the rotor slots are disposed with constant circumferential intervals therebetween, the stator slots are disposed with constant circumferential intervals therebetween, wherein a ratio of the number of the rotor slots to the number of the stator slots is set to a predetermined value larger than 1. a solid rotor extending axially and supported rotatably, including a shaft part and a columnar-shaped rotor core part integrally formed with the shaft part, the columnar-shaped rotor core part having a diameter larger than that of the shaft part and having rotor slots formed therein which are disposed with circumferential intervals therebetween and extend axially, and a plurality of conductor bars passing through the respective rotor slots and coupled together at both axial ends outside the rotor core part; a stator having a cylindrical stator core provided radially outside the rotor core part and stator windings passing through a plurality of respective stator slots which are formed in the radially inner surface of the stator core so as to be disposed with circumferential intervals therebetween and to extend axially; and two bearings supporting the solid rotor at both axial sides of the shaft part, sandwiching the rotor core part, wherein a virtual plane positioned at a center between two opposing and parallel to each other walls (14a, 14b) of each rotor slot is tilted at a predetermined angle with respect to a plane passing a rotation center axis of the solid rotor, and a radial outer end portion of each of the plurality of conductor bars is flush with the radially outer surface of the rotor core part forming a cylindrical shape, the rotor slots are disposed with constant circumferential intervals therebetween, the stator slots are disposed with constant circumferential intervals therebetween, wherein a ratio of the number of the rotor slots to the number of the stator slots is set to a predetermined value larger than 1.