A high-frequency treatment device includes a tubular body having a front end portion and a rear end portion an operating handle having a high-frequency port and a main push rod extending through the body, the operating handle slidably fitted to the body a front tube having a rear end portion connected to the front end portion of the body an auxiliary push rod rotatably connected to the main push rod, the auxiliary push rod extending into the front tube a wire fixed to the auxiliary push rod, the wire extending through the front tube a rotary knob rotatably attached to the body, the rotary knob configured to rotate together with the auxiliary push rod and the wire and an arc-shaped knife fixed to the wire and connected to the high-frequency port of the operating handle via the wire, the auxiliary push rod and the main push rod.
