A rotor core is configured by stacking a plurality of core plates each including: an inner peripheral side core portion; an outer peripheral side core portion; a magnet insertion hole; a radial connection portion to be connected to the inner peripheral side core portion; a circumferential connection portion to be connected between the outer peripheral side core portion and the radial connection portion, including a minimum width portion having a width smaller than widths at both ends, and having a width smoothly decreasing from both ends toward the minimum width portion; and a thin portion including a uniform thickness portion which is provided in the circumferential connection portion and which has a uniform thickness and a non-uniform thickness portion which is adjacent to the uniform thickness portion and which has an increasing thickness, the thin portion having the minimum width portion within the uniform thickness portion.