Abstract: A zoom lens system having two lens group. The zoom lens system has a zooming ratio greater than 2.4, a viewing angle of over 70 degrees and a telephoto ratio of about 1.0. The zoom lens system includes a first lens group of a positive refractive power, which has four lenses, and a second lens group of a negative refractive power, which has three lenses. The second lens group includes one aspherical lens surface. The zoom lens system according to the present invention satisfies the following conditions:0.22<fl/ft<0.302.45<ft/fw0.74<Ll1/(ft-fw)<0.850.75<fl/Y<1.10wherefl is a focal length of a first lens group;ft is a focal length of the entire zoom lens system at a telephoto position;fw is a focal length of the entire zoom lens system at a wide angle position;Ll1 is a shift distance of the first lens group during zooming; and2Y is a diagonal length of an image.