PURPOSE: To obtain a wide-angle zoom lens whose lens system is reduced in size on the whole by providing three lens groups in total and properly setting the lens constitution of the respective lens groups.

CONSTITUTION: This zoom lens has three lens groups which are a 1st group L1 with negative refracting power, a 2nd group L2 with positive refracting power, and a 3rd group L3 with negative refracting power in order from the object side and the power is varied by varying the intervals between the respective lens groups; and a condition is satisfied, where f1 is the focal length of the 1st group L1, fwW and fT are the focal lengths of the whole system at the wide-angle end and telephoto end, and Y is the diagonal length of an effective picture plane.