An image forming apparatus capable of preventing a developing cartridge mounted at the image forming apparatus from being damaged by an outside impact in a process of transporting the image forming apparatus. The image forming apparatus comprises at least one developing cartridge each having an image carrier to form an image, at least one supporting frame configured to support the at least one developing cartridge installed at an inside the body, and at least one buffer member configured to ease impact that occurs between the at least one developing cartridge and the at least one supporting frame by being disposed in between the at least one developing cartridge and the at least one supporting frame, the at least one buffer member provided to be removed before the at least one developing cartridge starts an initial printing operation.