A lens apparatus that can secure a necessary lens moving distance while avoiding growing in size and that is able to firmly hold a lens. The lens apparatus comprises a first lens group holding member, a second lens group holding member, an exterior cylinder disposed on an outer peripheral side of the first lens group holding member, a first cam cylinder disposed to be rotatable around an optical axis and movable in an optical axis direction corresponding to a rotation angle, a guide cylinder having a diameter fitting portion rotatably holding the first cam cylinder around the optical axis, and a second cam cylinder. The exterior cylinder does not have a cam groove or a guide groove for guiding another member, and is driven to a position at which part of the exterior cylinder is exposed to an outside corresponding to a rotation angle of the second cam cylinder.