To obtain a zoom lens which obtains sufficient brightness even in a telephoto end and reduces the change of brightness attendant on zooming from the wide angle end to the telephoto end while being made sufficiently small-sized and maintaining a high performance.

The zoom lens has a first negative optical system G1, a second positive optical system G2, and a third positive optical system G3 arranged in this order from the object side, and a stop FA moving together with the second optical system G2 as a single body is provided on the object side of the second optical system G2. When the power is varied from a short-focus end to a long-focus end, the second optical system G2 moves monotonously from the image side to the object side, and the first optical system G1 moves so as to correct the variation in the image surface position attendant on the power variation. The zoom lens satisfies conditional formulas 2.0<FT<3.0, 0.9<FT/FW<1.2, and 0.5<AW/AT<0.9, where FW, FT, AW, and AT are the minimum F number at the wide angle end, the minimum F number at the telephoto end, the maximum stop diameter at the wide angle end, and the maximum stop diameter at the telephoto end, respectively.