Abstract: A differential amplifier includes first and second normally off type MESFETs, which constitute a differential switching stage, sources of which are commonly connected to a current source, and gates of which are supplied with a signal input potential and a reference potential, respectively, third and fourth normally on type MESFETs connected at loads between the first MESFET and a voltage source and between the second MESFET and the voltage source, fifth and sixth normally off type MESFETs gates of which are connected to the drains of the first and second MESFETs, respectively, and drains of which are connected to the voltage source, and seventh and eighth MESFETs drains of which are connected to sources of the fifth and sixth MESFETs and output first and second output potentials and gates of which are applied with potentials having levels corresponding to the second and first output potentials, respectively.