PURPOSE: To provide the zoom lens which has both compactness and diversity of a plastic lens and is greatly reduced in cost as compared with a conventional lens although the lens has an about ×10-×12 high power variation ratio and brightness about F1.4 suitable to a small-sized video camera, etc.

CONSTITUTION: This zoom lens has a 1st lens group with positive refracting power, a 2nd group which has negative refracting power and is movable for power variation, a 3rd fixed lens group which has positive refracting power, and a 4th lens group which has positive refracting power and corrects a shift in the position of an image plane at the time of power variation in order from the object side, and the 4th lens group has at least two positive lenses and at least one negative lens; and plastic lenses are used as at least two of the lenses constituting the 4th lens group and at least two of the plastic lenses are cemented.