Patent ID: 8320799

Claim:
An image forming apparatus, comprising: a first image formation unit configured to form a black toner image; a second image formation unit configured to form component color toner images, said second image formation unit attachably detachable from the image forming apparatus; a first toner supply unit having a first toner container holder and configured to supply toner stored in a first toner container held on the first toner container holder to the first image formation unit; second toner supply units having second toner container holders and each configured to supply toner stored in second toner containers held on the second toner container holders to the second image formation unit, wherein each of said second toner supply units includes a first toner conveyance path configured to convey black toner to the first image formation unit when the second image formation unit is detached and the second toner containers held on the second toner container holders store the black toner, said second toner supply units each include a second toner conveyance path configured to convey component color toner to the second image formation unit when the second image formation unit is attached and the second toner containers held on the second toner container holders store the component color toner, wherein one of said first and second toner conveyance paths is selectively used in accordance with the detachment of the second image formation unit.