An image forming apparatus in which air or dust does not enter a recording liquid tube when an ink cartridge is changed is disclosed. An engine unit, in which an image forming section and a sub scanning direction paper carrying section are integrated as one unit, is removably attached to an apparatus main body of the image forming apparatus. Further, an ink cartridge storing section, in which an ink cartridge is removably stored, is integrated into the engine unit, and is changed together with the engine unit. In addition, a carriage, the recording liquid tube, and the ink cartridge storing section are removed as one unit from the engine unit.