A high magnification zoom lens is provided. The zoom lens includes a first lens group including a single positive lens and having a positive refractive power, a second lens group having a negative refractive power, a third lens group having the positive refractive power, a fourth lens group having the positive refractive power, and a fifth lens group having the positive refractive power. The first through fifth lens groups are sequentially arranged from an object side toward an image side. The first lens group, the second lens group, and the third lens group are moved in a direction of an optical axis to change magnification. The fourth lens group is moved to compensate for a movement of a focal position occurring during the magnification change, and the fifth lens group is fixed. Accordingly, the zoom lens is compact, has high magnification, and satisfies conditions of a long back focal length and telecentricity that are required when a solid image pickup device is used.