An HF surgical appliance comprising an HF generator having an output circuit, which contains an output transformer and has an output impedance. Output terminals, to which an HF surgical instrument can be connected, are provided, said instrument supplying a high-frequency current with a specific frequency into tissue to treat the same. An additional output circuit containing an additional transformer, which is connected between the output circuit and the output terminals to reduce the output impedance is also provided. In this way, the HF surgical appliance can be operated with a high power output even on loads having low impedance.
