A rotor comprising: - a stacked core formed by stacking a plurality of thin sheet cores each made of a magnetic thin sheet; - permanent magnets provided in magnet holes formed to penetrate in an axial direction in the stacked core; - end plates (100, 101) provided at both ends in the axial direction of the stacked core, the end plates (100, 101) being formed from a nonmagnetic thin-plate material such as a nonmagnetic SUS (stainless steel) thin plate; and - a rotary shaft provided in a through hole formed at a center in the stacked core and the end plates (100, 101), the rotary shaft fixing the stacked core and the end plates (100, 101), wherein - a plurality of the magnet holes in which the permanent magnets are provided are arranged in a circumferential direction, - void portions in which the permanent magnets are not present are provided at both ends in the circumferential direction of each magnet hole, - the stacked core has flow holes which penetrate in the axial direction and each of which is formed, between the magnet holes adjacent in the circumferential direction, on an inner side in a radial direction with respect to the magnet holes, - some or all of the thin sheet cores have first groove portions via which the void portions of the magnet holes and the flow holes communicate with each other, and second groove portions via which the void portions of the magnet holes and outer circumferences of the thin sheet cores communicate with each other and which serve as discharge ports, and the cores have flow paths formed through the flow holes, the first groove portions, the void portions, and the second groove portions so as to communicate with outside of the thin sheet cores in the radial direction, and at least one of the end plates (100, 101) has first holes through which the flow holes are exposed and which serve as intake ports, and tab portions which are located on downstream sides in a rotation direction of the first holes and which assist air intake wherein the flow holes and the first holes each have such a shape that a width in the radial direction is greater than a width in the circumferential direction. - a stacked core formed by stacking a plurality of thin sheet cores each made of a magnetic thin sheet; - permanent magnets provided in magnet holes formed to penetrate in an axial direction in the stacked core; - end plates (100, 101) provided at both ends in the axial direction of the stacked core, the end plates (100, 101) being formed from a nonmagnetic thin-plate material such as a nonmagnetic SUS (stainless steel) thin plate; and - a rotary shaft provided in a through hole formed at a center in the stacked core and the end plates (100, 101), the rotary shaft fixing the stacked core and the end plates (100, 101), wherein - a plurality of the magnet holes in which the permanent magnets are provided are arranged in a circumferential direction, - void portions in which the permanent magnets are not present are provided at both ends in the circumferential direction of each magnet hole, - the stacked core has flow holes which penetrate in the axial direction and each of which is formed, between the magnet holes adjacent in the circumferential direction, on an inner side in a radial direction with respect to the magnet holes, - some or all of the thin sheet cores have first groove portions via which the void portions of the magnet holes and the flow holes communicate with each other, and second groove portions via which the void portions of the magnet holes and outer circumferences of the thin sheet cores communicate with each other and which serve as discharge ports, and the cores have flow paths formed through the flow holes, the first groove portions, the void portions, and the second groove portions so as to communicate with outside of the thin sheet cores in the radial direction, and at least one of the end plates (100, 101) has first holes through which the flow holes are exposed and which serve as intake ports, and tab portions which are located on downstream sides in a rotation direction of the first holes and which assist air intake wherein the flow holes and the first holes each have such a shape that a width in the radial direction is greater than a width in the circumferential direction.