Motor rotor and method for correcting rotating balance thereof

The invention is characterized in that in a motor rotor constituted by a motor shaft, a permanent magnet surrounding the motor shaft around an axis, a pair of end rings surrounding the motor shaft around the axis and pinching the permanent magnet from both sides in an axial direction, and a hollow cylindrical outer sleeve surrounding the permanent magnet and a pair of end rings in a fastening state around the axis, one end portion or both end portions of the outer sleeve protrudes in the axial direction than an end surface of the end ring. A rotating balance correction is executed by pruning away a part of the protruding portion.