Image forming apparatus capable of making toner cartridge completely attached to drum cartridge during attachment of drum cartridge to housing

An image forming apparatus comprising:

• a housing comprising a side wall positioned at one end portion of the housing in a first direction;
• a drum cartridge attachable to the housing, the drum cartridge comprising:
• a photosensitive drum rotatable about a drum axis extending in the first direction;
• and
• a drum frame;
• a toner cartridge attachable to the drum cartridge, the toner cartridge comprising:
• a toner casing configured to accommodate toner therein;
• a toner memory;
• a memory holder holding the toner memory;
• and
• a memory holder cover movably holding the memory holder, the memory holder cover having a protrusion protruding in a direction crossing the first direction;
• and
• a contacting portion positioned at the side wall of the housing, the protrusion being configured to contact the contacting portion,
• wherein, in a case where the drum cartridge is to be attached to the housing while the toner cartridge is at a lifted-up position relative to the drum frame, the protrusion is configured to contact the contacting portion to move the toner cartridge from the lifted-up position to an attachment position where the toner cartridge is fully attached to the drum frame, the toner cartridge being lifted up from the drum frame at the lifted-up position rather than at the attachment position.