A miniature zoom lens system comprises three lens groups having four lenses in total. The first lens group has negative power and is fixed. The second lens group has positive power and includes two lenses. An aperture is furnished in front of and movable with the second lens group. The third lens group has positive power. The second and third lens groups are movable along an optical axis between a wide-angle position and a telephoto position. The system fulfills the following conditions: 11.5