An active inductance circuit comprising a signal terminal (OUT) and having voltage and current characteristics, as viewed from this terminal, which are identical to those of a circuit comprising an inductance, this active inductance circuit having a structure in which the drain terminal of a first MOS transistor M1 and the gate terminal of a second MOS transistor M2 different in conductivity type from the first MOS transistor are connected to the signal terminal, the gate terminal of the first MOS transistor is connected to the source terminal of the second MOS transistor, a capacitor and a current source are connected to the source terminal of the second transistor, the source terminal of the first MOS transistor and the drain terminal of the second MOS transistor are connected to a power source and other terminals of the capacitor and current source are connected to another power source.