A zoom lens includes 10 or less lens elements and having a zoom ratio of more than 20.times., said zoom lens having first, second, third, and fourth groups of lens elements placed in turn from object side to image side; wherein the first group of lens elements has positive refractive power and is fixed in position during zooming; wherein the second group of lens elements has negative refractive power and is moved in position during zooming; wherein the third group of lens elements has positive refractive power, includes at least one aspheric surface, and is fixed in position during zooming; wherein the fourth group of lens elements has positive refractive power, includes at least one aspheric surface, corrects variations in image surface position during zooming, and performs focusing; and wherein the zoom lens satisfies the following conditional expression (1):<< ##EQU00001## where dz is the movable distance of the second group of lens elements to perform zooming and fw is the focal distance of the whole lens system at a wide angle end.

 
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