A zoom lens barrel structure includes a first lens frame including an outer ring portion, an inner ring portion, a flange wall, and a first cam follower; a cam ring positioned between the outer and inner ring portions; a second lens frame having a second cam follower, positioned inside the inner ring portion; a first cam groove formed on an outer peripheral surface of the cam ring, the first cam follower being engaged in the first cam groove; a second cam groove formed on an inner peripheral surface of the cam ring so that the second cam follower engages in the second cam groove; a linear guide ring, positioned around the first lens frame; and a linear guide mechanism, provided between the inner ring portion of the first lens frame and the second lens frame, for guiding the second lens frame linearly along the optical axis.