The invention relates to an electrosurgical instrument for cutting and/or coagulating a tissue to be treated, comprising at least one cutting electrode for conducting a high-frequency (“HF”) current through the tissue for carrying out a cutting process and comprising power supply devices for supplying the HF current at least to the cutting electrode. The design of the electrosurgical instrument is improved so that the cutting process can be carried out with an increased reliability while prolonging the serviceable life of the cutting electrode at the same time. To this end, the cutting electrode is mounted on the electrosurgical instrument in a manner that enables it to rotate about a rotation axis and comprises at least one cutting area which is provided in the form of a helical curve or similar three-dimensional curve running around the rotation axis and which is arranged in such a manner that when the cutting electrode rotates about the rotation axis it is active over its length in sections on the tissue when a section falls below a defined minimum distance from the tissue and/or is located within a defined window area.
