A rotor of a rotating electrical machine includes: a magnet; and a rotor yoke including at least a first core block and a second core block formed by stacking steel plates, each of the steel plates includes an opening portion serving as a coolant flow path, the opening portion positioned on an outermost diameter side includes an outer-diameter-side inner wall portion with a predetermined width in a circumferential direction and located on an imaginary circle centered on an axis of the rotor, the second core block is arranged adjacent to the first core block while the second core block is rotated by a predetermined angle with respect to the first core block, and the predetermined width is a length at which the outer-diameter-side inner wall portions of the opening portions of the first core block and the second core block overlap each other when seen from the axial direction.