An endless belt confronts the photosensitive drum. A developing unit includes a developer accommodation portion that is configured to accommodate developer, and a developing roller that is rotatably provided and supplies the photosensitive drum with the developer. A collecting unit is configured to remove waste developer to be discarded from the endless belt and to collect the waste developer. A waste developer accommodation portion is provided integrally with the developer accommodation portion and is configured to accommodate the waste developer collected by the collecting unit. A conveying mechanism is configured to be connected to both the waste developer accommodation portion and the collecting unit and to convey the waste developer from the collecting unit to the waste developer accommodation portion. The waste developer accommodation portion is movable relative to the conveying mechanism.