An ink supply device includes: an ink cartridge including a port which is provided in a rear surface thereof at a lower portion of the ink chamber and which allows ink to flow in an ink flow direction and an engaged portion which is provided on an upper surface thereof; a cartridge mounting portion into which the ink cartridge is insertable in an insertion direction wherein the cartridge mounting portion is configured to accommodate the ink cartridge movably between a first posture and a second posture; a joint which is provided in the cartridge mounting portion and is connected to the port; a first elastic member which urges the ink cartridge to a removal direction; and a lock member which is engaged with the engaged portion to prevent the ink cartridge from being moved in the removal direction by the urging force of the first elastic member.