A bending device to bend a flexible tube from inside electrically includes an electric actuator to drive a movable shaft electrically along the longitudinal direction of the tube in the axial direction and in the rotational direction, and an elongated member of which one end is connected to the movable shaft and the other end is connected to the inner surface of the tube at the location distanced, in the longitudinal direction of the tube, from the connecting point connecting the one end of the elongated member and the movable shaft, the connecting point connecting the one end of the elongated member and the movable shaft being located eccentric to the center of the movable shaft so that the towing direction of the elongated member towed by retreating the movable shaft changes along the circumferential direction by rotation of the movable shaft.
