An image pickup apparatus of the present invention varies optical properties by moving a part of lenses of an objective lens, and includes a solid-state image pickup device unit that is disposed at a rear-end section and that subjects a subject image to photoelectric conversion, a fixed lens frame that retains the objective lens that is disposed in front of the solid-state image pickup device unit, a movable lens frame that retains the part of lenses that moves along a photographing optical axis O inside the lens frame, and an actuator having one end connected to the movable lens frame and that moves the movable lens frame forward and backward. The actuator includes a rigid member provided so as to extend to the vicinity of the rear end at which the solid-state image pickup device unit is disposed and a shape memory alloy that is coupled to the rigid member.