A lens barrel includes a barrel member including an optical system and a barrier device mounted thereto. The barrier device includes blades that are openable/closable to protect a front surface of the optical system, a cover member having an opening portion for allowing light to pass therethrough, and a barrier driving member configured to drive the barrier blades such that the blades are revolvable around an optical axis. Size of shielded area is defined when the blades are fitted together after rotating corresponding to a range capable of shielding the opening portion. Rotation shafts are configured to allow the blades to rotate therearound to be opened/closed and are pivotally mounted on the barrier driving member. The barrier driving member is configured to rotate to bring the blades into a closed state in such a manner as to shield a gap made between the shielded area and the opening portion.