A lens barrel includes a rotatable ring, a non-rotatable outer annular member having a circumferential groove located on the inner peripheral surface thereof, an advancing/retracting mechanism configured to move the rotatable ring along the optical axis between movement limits of the rotatable ring, a rotational projection located on the outer peripheral surface of the rotatable ring such that the projection is engaged in the circumferential groove when the rotatable ring is moved to one of the movement limits, and a stopper which is insertable into and removable from the circumferential groove at an intermediate point between opposite ends of the groove. The stopper limits the range of rotation of the rotatable ring relative to the outer annular member by engaging the rotational projection in a state where the stopper is positioned in the circumferential groove, and the stopper stops preventing the range of rotation of the rotatable ring in a state where the stopper is positioned outside the circumferential groove.