This endoscopic energy treatment instrument includes: a treatment instrument insertion part having flexibility and having a power reception part that is capacitively coupled by facing to a power transmission electrode arranged in a treatment instrument channel provided in an endoscope a treatment part that is arranged on a distal end of the treatment instrument insertion part, and that uses electric power supplied from the power reception part to perform energy treatment and a cleaning part that is arranged on the treatment instrument insertion part between the power reception part and the treatment part so as to be able to come into contact with the treatment instrument channel, the cleaning part being configured to clean an inside of the treatment instrument channel in accordance with a movement of the treatment instrument insertion part.
