Image forming apparatus capable of resetting and decreasing a surface potential of a photosensitive member

An image forming apparatus including: a plurality of photosensitive members on which electrostatic latent images are formed; a plurality of charge units to charge the respective photosensitive members with an electric potential; at least one exposure unit which irradiates light to the respective photosensitive members; a plurality of developer supply devices, which adhere a developer to the respective photosensitive members, to form visible images on a surface of the respective photosensitive members; a transfer unit, which transfers the visible images formed on the respective photosensitive members to a transfer medium; and a plurality of exposure lamps which are mounted between the plurality of photosensitive members. Each of the exposure lamps radiates light to the surface of one of two adjacent photosensitive members, after completion of the transfer, to reset a surface potential thereof, and irradiates light to the surface of the other photosensitive member, on which the visible image is formed, to decrease a surface potential thereof.