An endoscope apparatus includes a front end section which is rigid, and a flexible tube which has a bent portion. One end of a tube which can be bent is fixed to a lens barrel which holds an optical mechanism having a movable section. The tube is extended in a longitudinal direction of the flexible tube of the endoscope apparatus, and at least a part of a shape memory element is accommodated inside the tube. One end of the shape memory element is fixed to an end of the tube, which is not fixed to the lens barrel, and the other end of the shape memory element is mechanically connected to the movable section of the optical mechanism which includes the movable section. Due to expansion (elongation) and contraction of the shape memory element, relative positions of the movable section of the optical mechanism which includes the movable section, and one end of the tube fixed to the lens barrel are changed.
