Providing a zoom lens system being compact and simple having excellent optical performance suitable for an optical apparatus with a limited space for a zoom lens, and capable of shifting an image, and an optical apparatus equipped therewith. The system includes, in order from an object: a first group having positive power and an optical path bending element; a second group having negative power; a third group having positive power; and a fourth group having positive power. Upon zooming from a wide-angle end to a telephoto end, the first and third groups are fixed relative to an image plane, the second group and the fourth group are moved along the optical axis, an image on the image plane can be shifted by shifting the third group or a portion thereof substantially perpendicularly to the optical axis. The first group includes at least one negative lens, and satisfies a given condition.