Abstract: A lens barrel includes an outer barrel provided on an inner periphery with a first thread and at least one linear guide groove intersecting the first thread and extending in a direction of an optical axis of the lens barrel, a middle barrel provided on an outer periphery with a second thread meshing with the first thread, and an inner barrel positioned inside the middle barrel. The inner barrel is provided with at least one follower which engages with the at least one linear guide groove, so that the inner barrel is guided along the optical axis without rotating about the optical axis with respect to the outer barrel. The lens barrel is also provided with a recess formed at a front end of each of the at least one linear guide groove on the inner periphery of the outer barrel. The recess has a width dimension which enables rotational movement of the at least one follower into the at least one linear guide groove during initial meshing of the middle barrel with the outer barrel.