Image forming apparatus having image forming units perpendicular to developer supply units

An image forming apparatus comprising:

• a plurality of image forming units, each having an image carrier and a developing device for developing latent images on the image carrier, the image forming units capable of being detachably attached in a predetermined direction to the image forming apparatus;
• and
• a plurality of developer supplying units arranged corresponding to each of the image forming units for supplying developer to the image forming units, the developer supplying units capable of being detachably attached in the predetermined direction to the image forming apparatus,
• wherein the image forming units and the developer supplying units are alternately so disposed that one end in a longitudinal direction of the respective image forming units intersects with one end in a longitudinal direction of the respective developer supplying units, and the image forming units and the developer supplying units are so disposed that the longitudinal direction of the respective developer supplying units is substantially perpendicular to the longitudinal direction of the respective image forming units, the developer is supplied at portions where the respective developer supplying units and the respective image forming units intersect, and the respective developer supplying units and the respective image forming units are respectively disposed so as not to overlap in movement paths related to attaching or detaching operations and each of said developer supplying units and image forming units is independently detachably attached.