A lens barrel includes a radially-retractable optical element constituting a part of a photographing optical system, the radially-retractable optical element being movable between a photographing position located on an optical axis of the photographing optical system, and a radially-retracted position located on an off-optical-axis position; a swing member which is rotatable about a rotation axis extending parallel to the optical axis, the swing member being associated with the radially-retractable optical element so as to move the radially-retractable optical element from the photographing position to the radially-retracted position by a forward rotation thereof and from the radially-retracted position to the photographing position by rearward rotation thereof; and a retracted position holding device for maintaining the radially-retractable optical element in the retracted position when the swing member further rotates in the forward direction even after the radially-retractable optical element reaches the radially-retracted position from the photographing position.