A developing device has a bearing member that can bear a toner, a storing chamber for storing the toner, a waiting chamber disposed below the storing chamber for receiving the bearing member that can be filled with the toner and a buffer chamber positioned between the storing chamber and the waiting chamber for storing the developer material. A first horizontal connecting path connects upper portions of the storing and buffer chambers, and two second connecting paths connect lower portions of the buffer chamber and the waiting chamber. A feed member feeds toner from the storing chamber through the first connecting path into the buffer chamber. A first conveying member in the buffer chamber conveys the toner from one of the connecting paths to the other of the connecting paths, and a second conveying member in the waiting chamber conveys the toner within the waiting chamber in the opposite direction.