A development device is attachable to and detachable from an apparatus main body in an inserting/drawing direction. The development device includes a holder portion, a hook, a lever portion, and an elastic arm portion. The holder portion supports a board connectable to a controller of the apparatus main body. The hook is engageable with a recess of the apparatus main body. The lever portion is provided with the hook. At least one elastic arm portion connects the holder portion and the lever portion. In a middle of an attachment to the apparatus main body, the hook interferes with the apparatus main body to shift the lever portion in a direction crossing the inserting/drawing direction and to elastically deform the elastic arm portion. When the hook is engaged with the recess, the elastic deformation of the elastic arm portion is released and the board is connected to the controller.