An image forming apparatus comprising an electrophotographic photoreceptor, a charging unit, an exposure unit, a development unit, and a transfer unit, wherein the image forming apparatus conducts charging, exposure, development, and transfer while moving a circumferential surface of the electrophotographic photoreceptor in a predetermined direction, the image forming apparatus further comprises a controlling unit which controls a moving velocity of the circumferential surface of the electrophotographic photoreceptor so that a time required for processes from charging to development is changeable, the electrophotographic photoreceptor includes an undercoat layer and a photosensitive layer, and the undercoat layer includes a metal oxide particle and an acceptor compound having a group capable of reacting with the metal oxide particle.