ROTOR, MOTOR, COMPRESSOR, AND AIR-CONDITIONING DEVICE

Provided is a rotor of a motor, capable of suppressing a decrease in the amount of magnetic flux generated from a magnet while reducing the influence of demagnetization. A rotor (10) is provided so as to be rotatable about an axis (C), and includes a permanent magnet (40) and a rotor core (20). The permanent magnet (40) has a demagnetization portion (40a) disposed near the outer peripheral surface of the rotor (10) when viewed along the axis (C). The rotor core (20) forms a magnetic flux barrier (24) which is a hole or cutaway disposed near the demagnetization portion (40a) when viewed along the axis (C). The magnetization direction of the demagnetization portion (40a) is oriented in the circumferential direction of the rotor (10). The rotor (10) has a cylindrical shape with a radius R. A relational expression of 0 < L/R ≤ 0.08 is satisfied where L is the dimension of the magnetic flux barrier (24) in the direction in which the demagnetization portion (40a) extends when viewed along the axis (C).