A plasma surgery apparatus includes an HF generator for generating an HF activation signal, a gas source for providing a plasma gas, and a plasma applicator having a channel which opens out at a distal end of the applicator and through which the plasma gas can flow. The apparatus also includes an HF electrode that is electrically connected to the HF generator. When the HF electrode is supplied with the HF activation signal, a plasma is provided originating from the distal end of the applicator. The apparatus also includes a control unit and a flow regulator for regulating a flow rate the plasma gas in the channel. The control unit receives or requests an operating variable of the HF generator and, according to a saved functional relationship, controls the flow regulator so that the flow rate of the plasma gas is correlated with a detected value of the operating variable.