An image forming unit includes a first unit and a second unit. The first unit includes a first engagement portion and a rotatably supported image bearing body. An electrostatic latent image is formed on the image bearing body. A second unit includes a second engagement portion and a rotatably supported developer material bearing body. The developer bearing body develops the electrostatic latent image with a developer material into a developer image. The second unit is coupled to the first unit such that the first engagement portion engages the second engagement portion. A plurality of urging members that are mounted in a vicinity of one end of an axis of rotation of developer material bearing body, and urge the first unit and the second unit in directions such that the image bearing body and the developer material bearing body are urged against each other.