The conventional varifocal glasses has a structure where there are two or more lenses whose focal length are different each other. In these days, many people use a varifocal glasses to correct presbyopia and other disorders of accommodation. However, it needs very long time to well use the varifocal glasses. Moreover, the structure of the conventional varifocal glasses not only makes users dizzy but also limits the field of view of users. Adaptive lens whose focal length is changed by the input voltage can be a solution to solve the above problems. In this paper, we propose a tiny adaptive lens for varifocal glasses, which can be altered its focal length by various voltage inputs. The proposed adaptive lens is composed of an electroactive polymer gel, which is fabricated by mixing poly(vinyl chloride) and plasticizer. When we applied the voltage input to the proposed electroactive polymer gel based adaptive lens, the electroactive polymer gel is deformed toward anode so its curvature can be adjusted. We conduct experiments to investigate the zoom effect and the focal length variation of the developed adaptive lens. From the result, the focal length of the proposed lens is changed by the applied voltage. Furthermore, we could observe that the image from the proposed lens becomes zoom in/out according to the focal length’s variation. If the proposed lens is applied to varifocal glasses, it can offer an opportunity to identify objects in various distances for presbyopic users.