A drive circuit for a gate turnoff thyrister (GTO) having a combination of a first switching element and a primary coil of a reactor connected in series between the anode of a power source and the gate electrode of the GTO, a secondary coil of the reactor magnetically coupled with the primary coil thereof and a second switching element connected in series between the gate electrode and cathode of the GTO and adapted to turn "on" at or above a predetermined voltage. By turning the first switching element on, a forward drive direction primary current of the GTO is generated and flows from the power source and through the primary coil to the gate of the GTO to allow a main circuit current to flow through the GTO. By turning the first switching element off, a reverse drive direction reactor current in the secondary coil of the reactor when the forward drive direction primary current flowing through the primary coil has been interrupted is generated and flows from the cathode of the GTO toward the gate electrode of the GTO through the second switching element to turn the GTO off so that the main circuit current through the GTO is interrupted.