PURPOSE: To provide a zoom lens without losing the compactness even when a first group is fixed at the time of zooming and holding high optical performance by giving one and more positive and negative lenses to a second group, respectively and satisfying a specified condition.

CONSTITUTION: In the zoom lens comprising a first group Gr1 having a negative refractive power, a second group Gr2 having a positive refractive power and a third group Gr3 having a negative refractive power and performing the zooming operation by changing the intervals of the respective groups, one and more positive lenses and negative lenses are included in the second group Gr2, the conditional relations: 0.08<t1/y'<0.25, 0.08< t2/y'<0.28 are satisfied. Here, t1, t2 are the thicknesses of the first group Gr1 and the second group Gr2 on the optical axis, respectively, and y' is a diagonal length on a film plane. Consequently, the zoom lens without losing the compactness even when the first group is fixed at the time of zooming and holding high optical performance is obtained.