An electric motor comprising: a frame supporting a stator; a bracket and an end plate configured to close respective ends of the frame; a first bearing housing and a second bearing housing respectively retaining bearings (6, 7), and respectively fixed to the bracket and the end plate from an outside; a rotor shaft arranged inside the frame and rotatably supported by the bearings (6, 7); a rotor attached to the rotor shaft and opposing the stator; a first supporting body (23, 40) and a second supporting body (24, 42) attached to the rotor shaft at respective sides of the rotor; the supporting bodies (23, 40, 42, 24) respectively including tapered supporting surfaces (23a, 24a, 34a, 40a, 42a) having the rotor shaft as a center; and a plurality of threaded holes for fixing formed respectively in the bracket and the end plate in a manner penetrating in an axial direction parallel to the shaft, to oppose the supporting surfaces (23a, 24a, 34a, 40a, 42a, 36a, 36b), and into which bolts (27, 28) for fixing the rotor that press the supporting surfaces (23a, 24a, 34a, 40a, 42a) are configured to be screwed from outside, characterized in that the first supporting body (23, 40) is formed as a first separating plate formed in a substantially funnel shape and extending tiltingly from a rotor core side toward the bracket, the second supporting body (24, 42) is formed as a second separating plate formed in a substantially funnel shape and extending tiltingly from the rotor core side toward the end plate, the supporting surface is positioned at least at a part on a circumference of the funnel shape of the second separating plate, the circumference having the rotor shaft as a center, and the plurality of threaded holes for fixing are formed in the bracket and the end plate so as to align on circumferences having the rotor shaft as centers and the funnel shape of the first separating plate comprises a side surface facing the outside, and a plurality of fins formed on the side surface and extending radially with the rotor shaft as a center, and the tapered supporting surfaces are formed on the fins. a frame supporting a stator; a bracket and an end plate configured to close respective ends of the frame; a first bearing housing and a second bearing housing respectively retaining bearings (6, 7), and respectively fixed to the bracket and the end plate from an outside; a rotor shaft arranged inside the frame and rotatably supported by the bearings (6, 7); a rotor attached to the rotor shaft and opposing the stator; a first supporting body (23, 40) and a second supporting body (24, 42) attached to the rotor shaft at respective sides of the rotor; the supporting bodies (23, 40, 42, 24) respectively including tapered supporting surfaces (23a, 24a, 34a, 40a, 42a) having the rotor shaft as a center; and a plurality of threaded holes for fixing formed respectively in the bracket and the end plate in a manner penetrating in an axial direction parallel to the shaft, to oppose the supporting surfaces (23a, 24a, 34a, 40a, 42a, 36a, 36b), and into which bolts (27, 28) for fixing the rotor that press the supporting surfaces (23a, 24a, 34a, 40a, 42a) are configured to be screwed from outside, characterized in that the first supporting body (23, 40) is formed as a first separating plate formed in a substantially funnel shape and extending tiltingly from a rotor core side toward the bracket, the second supporting body (24, 42) is formed as a second separating plate formed in a substantially funnel shape and extending tiltingly from the rotor core side toward the end plate, the supporting surface is positioned at least at a part on a circumference of the funnel shape of the second separating plate, the circumference having the rotor shaft as a center, and the plurality of threaded holes for fixing are formed in the bracket and the end plate so as to align on circumferences having the rotor shaft as centers and the funnel shape of the first separating plate comprises a side surface facing the outside, and a plurality of fins formed on the side surface and extending radially with the rotor shaft as a center, and the tapered supporting surfaces are formed on the fins.