A zoom lens system includes: a first lens group having positive power; a second lens group having negative power; a third lens group having positive power; a fourth lens group having positive power; a fifth lens group having negative power; and a following lens group following the fifth lens group. The first to fifth lens groups and the following lens group are arranged in this order such that the first lens group is located closest to an object and that the following lens group is located closest to an image. While the zoom lens system is zooming, intervals between the respective lens groups change. While the zoom lens system is focusing from an infinity focus point through a shortest shooting range, a plurality of negative lens groups included in the fifth lens group and the following lens group move.