A method of making an incision in an organ includes piercing, by a puncture needle having a proximal end and a distal end, an abdominal wall and an organ that is to be incised, disposing, via the puncture needle, an electrode, to which a first end of a cable is electrically connected, inside the organ, and disposing a second end of the cable outside a body, performing insufflation using a conduit so as to form a space between the abdominal wall and the organ, pulling the cable farther from the second end so that the electrode is placed in contact with an incision position of the organ, and the incision position of the organ is pulled into the space, and supplying power to the cable so that an incision is made by the electrode at the incision position of the organ.
