A lens barrel and imaging device advantageous for making unnatural brightness variation in an image, due to a liquid-crystal light control element, less noticeable, while reducing the size of an optical system, are disclosed. A lens barrel comprises an optical system, a rectangular planar liquid-crystal light control element, and an imaging element. An object image captured by the optical system is guided to the imaging element through the control element comprising a liquid crystal layer sealed in between a pair of alignment layers and containing rod-shaped liquid crystal molecules. A sensor unit of the imaging element has a rectangular imaging area. Light rays guided from the optical system to the imaging element diverge away from an optical axis. An orientational direction of the control element is substantially parallel to the shorter sides of the imaging area.