A differential amplifier circuit arrangement provided with first and second field effect transistors having their sources coupled together in common, the drain of the first field effect transistor being connected to the emitter of a bipolar transistor whose collector is connected via a drain load for this field effect transistor to a power supply line and whose base is held at a constant potential with respect to the commonly coupled sources, the drain of the second field effect transistor being coupled to the power supply line without a voltage stabilizing transistor. The bipolar transistor serves to stabilize the drain-source voltage of the first field effect transistor, thus maintaining constant the input impedance of the amplifier measured at the gate of the first field effect transistor. The differential transistors may be bipolar transistors.