A rotor of a rotating electrical machine includes a substantially annular rotor core and a plurality of magnetic pole portions formed at predetermined intervals in a circumferential direction of the rotor core. Each magnetic pole portion includes an outer diameter side magnet portion configured by an outer diameter side circular arc magnet arranged so as to protrude radially inward and an inner diameter side magnet portion located radially inward of the outer diameter side magnet portion and configured by a pair of inner diameter side arc magnets arranged so as to radially inward of the radially outer magnet portion. Each arc magnet is an arc magnet in which an inner peripheral surface and an outer peripheral surface have the same arc center.