An electric motor having a permanent magnet and a compressor including an electric motor are provided. The electric motor may include a stator; and a rotor rotatably disposed and spaced a predetermined gap apart from the stator. The rotor may include a rotational shaft, a permanent magnet arranged concentrically to the rotational shaft, and a permanent magnet support that supports the permanent magnet. The permanent magnet may have a cylindrical shape and be magnetized to have polar anisotropy such that a magnetic field is formed on the magnet's surface facing the gap but is not formed on the magnet's surface opposite to the gap. The permanent magnet support may be configured to form no flux path in the permanent magnet and connect the rotational shaft to the permanent magnet. Thus, the rotor has a reduced weight with consequent suppression of vibration and noise.