To provide a non-reciprocal circuit element which is remarkably smaller than a conventional one and is excellent in mass-productivity.

The circuit element includes a magnetic rotor 1, a permanent magnet 2 and yokes 31, 32. The permanent magnet 2 is provided on at least one surface side of the magnetic rotor 1 and applies a DC magnetic field to the magnetic rotor 1. The yokes 31, 32 constitute a magnetic path for a magnetic field generated by the permanent magnet 2. In the permanent magnet 2, at least one side surface is exposed to the outside to form an external wall surface.