A lens barrel having a configuration lending itself to effectively reducing the size thereof and ensuring appropriate and safe operation thereof. The lens barrel includes a guiding portion provided for a lens holding member for guiding a cam follower in a radial direction of a cam barrel; a tabular elastic member provided for the lens holding member for urging the cam follower in a guiding direction of the guiding portion; and a regulating member limiting the transfer of the cam follower that is to be moved in a direction opposite to the urging direction by the elastic member. The regulating member is configured to be brought into contact with a predetermined portion of the lens holding member.