A permanent magnet embedded motor comprising: a stator in which a plurality of teeth sections, around which stator winding is wound, are arranged in a circumferential direction at equal angle intervals via slot sections; and a rotor in which a plurality of permanent magnets are embedded at the equal angle intervals in the circumferential direction, the rotor being rotatably held on an inner circumferential surface of the stator, wherein an outer circumferential surface of the rotor includes a plurality of divided outer circumferential surfaces corresponding to the plurality of permanent magnets, respectively wherein each of the plurality of divided outer circumferential surfaces includes: a first curved surface formed from a circumferential direction center of the divided outer circumferential surface toward circumferential direction both ends of the divided outer circumferential surface, a radial direction distance (b) between the first curved surface and the inner circumferential surface of the stator being kept fixed; second curved surfaces connected to both ends of the first curved surface, respectively; and third curved surfaces connected to both ends of the second curved surfaces, respectively, characterised in that the third curved surfaces are formed by a substantially fixed arcuate surface having the axis of the rotor as a central axis, a radial direction distance (a) between the arcuate surface and the inner circumferential surface of the stator being larger than the radial direction distance(b), and a distance between the points where the second curved surfaces are connected to the third curved surfaces (X-Y) is smaller than width of the permanent magnets in a direction orthogonal to a radial direction in the circumferential direction center of the divided outer circumferential surface, wherein the first curved surface has the axis of the rotor as a central axis and has a radial direction distance (r1,r3) from the axis of the rotor in the circumferential direction center of the divided outer circumferential surface as a radius, and wherein each of the second curved surfaces has a radius smaller than the radius of the arcuate surfaces forming the third curved surfaces. a stator in which a plurality of teeth sections, around which stator winding is wound, are arranged in a circumferential direction at equal angle intervals via slot sections; and a rotor in which a plurality of permanent magnets are embedded at the equal angle intervals in the circumferential direction, the rotor being rotatably held on an inner circumferential surface of the stator, wherein an outer circumferential surface of the rotor includes a plurality of divided outer circumferential surfaces corresponding to the plurality of permanent magnets, respectively wherein each of the plurality of divided outer circumferential surfaces includes: a first curved surface formed from a circumferential direction center of the divided outer circumferential surface toward circumferential direction both ends of the divided outer circumferential surface, a radial direction distance (b) between the first curved surface and the inner circumferential surface of the stator being kept fixed; second curved surfaces connected to both ends of the first curved surface, respectively; and third curved surfaces connected to both ends of the second curved surfaces, respectively, a first curved surface formed from a circumferential direction center of the divided outer circumferential surface toward circumferential direction both ends of the divided outer circumferential surface, a radial direction distance (b) between the first curved surface and the inner circumferential surface of the stator being kept fixed; second curved surfaces connected to both ends of the first curved surface, respectively; and third curved surfaces connected to both ends of the second curved surfaces, respectively, characterised in that the third curved surfaces are formed by a substantially fixed arcuate surface having the axis of the rotor as a central axis, a radial direction distance (a) between the arcuate surface and the inner circumferential surface of the stator being larger than the radial direction distance(b), and a distance between the points where the second curved surfaces are connected to the third curved surfaces (X-Y) is smaller than width of the permanent magnets in a direction orthogonal to a radial direction in the circumferential direction center of the divided outer circumferential surface, wherein the first curved surface has the axis of the rotor as a central axis and has a radial direction distance (r1,r3) from the axis of the rotor in the circumferential direction center of the divided outer circumferential surface as a radius, and wherein each of the second curved surfaces has a radius smaller than the radius of the arcuate surfaces forming the third curved surfaces.