An endoscope includes a fixed barrel non-turnably provided at a distal end portion of an insertion portion, an image pickup unit held to the fixed barrel, a movable barrel including a channel holding hole for holding a distal end of a treatment instrument channel inserted through the insertion portion, the movable barrel being supported by the fixed barrel so as to be turnable around an optical axis of the image pickup unit and being located closer to a distal end side than the fixed barrel, and a power transmission mechanism that transmits, to the movable barrel, power for causing the movable barrel to turn.
