In a non-reciprocal circuit device, a first center conductor, a second center conductor, and a third center conductor are disposed on a ferrite, to which a direct current magnetic field is applied by a permanent magnet, so as to be insulated from one another and so as to intersect with one another. One end of the first center conductor defines a first port, one end of the second center conductor defines a second port, and one end of the third center conductor defines a third port. The first port is connected to a first terminal, the second port is connected to a second terminal, and the third port is connected to a third terminal. The other ends of the respective center conductors are connected to one another, which is connected to a ground. Capacitance elements are connected in parallel to the respective center conductors.