DEVELOPING DEVICE

PURPOSE:To provide a developing device in which image density on both sides of a recording paper is prevented from lowering in comparison with a width central part. CONSTITUTION:This developing device is provided with a housing 1 which has an aperture part facing to an image carrier and which stores the developer inside, a developing roller 2 which is arranged at the aperture part of the housing 1 and carries the developer to the image carrier, and a brush roller 3 which is arranged in the housing 1 and supplies the developer to the developing roller 2. The brush roller 3 is constituted of a brush roller main body 11 and a brush 12 provided on the outer peripheral surface of the main body 11. The outside diameter of both end parts 11a of the main body 11 is formed to become larger and larger toward the end, and the length of the brush 12 formed at both end parts 11a of the main body 11 is made to be shorter and shorter toward the end.