A lumped element non-reciprocal circuit device is downsized without an increase in an insertion loss. A lumped element non-reciprocal circuit device comprises a plurality of center electrodes; a microwave magnetic material; a permanent magnet; and a metal case that serves as a magnetic yoke, wherein the center electrode is disposed on a main surface of the microwave magnetic material, the microwave magnetic material has a side surface perpendicular to the main surface, and a shortest distance between the side surface of the microwave magnetic material and the metal case is set to be equal to or larger than a thickness of the microwave magnetic material and equal to or smaller than 2.3 times of the thickness of the microwave magnetic material.