An irreversible circuit element includes first and second high pass isolators each including first and second center electrodes intersecting with and being insulated from each other on a ferrite to which a direct-current magnetic field is applied with a permanent magnet. One end of the first center electrode is an output port and the other end thereof is an input port, and one end of the second center electrode is another output port and the other end thereof is a ground port. A pass frequency band of the first isolator is higher than a pass frequency band of the second isolator. Respective output portions of the first and second isolators are electrically connected and defined as one output terminal, and a low pass filter LPF is inserted between the output terminal and the output port of the second isolator.