PURPOSE: To provide a current output circuit in which an effect for reducing a difference between positive and negative output current values resulting from an Early's effect can be obtained, and a variable impedance circuit in which output offset currents resulting from the Early's effect can be reduced.

CONSTITUTION: A transistor 7 whose base is connected to an equivalent voltage source is connected to the input side of a current mirror circuit equipped with transistors 7 and 8 whose electrical conductivity is different mutually at the collector and emitter of the transistor 7. Also, this circuit is equipped with a current output circuit 20 having respectively two positive and negative current output terminals, and two diode connected transistors 15 and 16 or diode, and the cathode sides of the diodes are commonly connected to the two current syringe terminals of the current output circuit 20, and the anode sides are connected to the different positive current output terminals of the current output circuit 20.