A lens barrel including a base and a collapsible barrel provided so as to collapse into and expand out of the base, the barrel including a lens constituting an image-capturing optical system for introducing an image of an object, a lens frame for holding the lens, and an operational unit provided in the lens frame for performing an operation relating to image capture based on a control signal supplied thereto, the lens barrel including a flexible substrate provided within the lens barrel for supplying the control signal from an electric circuit provided outside the barrel to the operational unit; wherein the flexible substrate has a first interconnect section to which the control signal is supplied; and a second interconnect section provided separately from the first interconnect section and having an end connected onto the lens frame and another end electrically connected to a ground potential.