A high image quality electrophotographic image forming apparatus is provided without increasing the size and cost, and reducing the life thereof. The potential difference (contrast potential) between a photoreceptor and a development roller for supplying toner to the photoreceptor by the use of a carrier is set to be smaller in the non-image area irrelevant to the printing operation, and set to be larger in the image area relevant to the printing operation. In this manner, the damage to the photoreceptor caused by the adhesion of the carrier is reduced in the non-image area irrelevant to the printing operation, and the fog is reduced in the image area relevant to the printing operation.