To prevent a pouch pack from being damaged by impact or the like during conveyance by surely making an RFID function even though film material of the pouch pack includes a conductive layer.

This invention is an ink jet type image forming apparatus including an ink container 22, and a container mounting part 32 to/from which the ink container is attached and detached to perform radio communication between an RFID tag 56 of the ink container 22 and an RFID detection substrate 36 of the container mounting part 32. The ink container 22 includes a pouch pack 48, and a container case 47 including the pouch pack 48, the RFID tag 56 is fixed to one wall part of the container case 47, and the container case 47 is provided with engagement parts 58, 61, 63 engaged with the pouch pack 48 to maintain a distance X between the RFID tag 56 and the pouch pack 48 at a fixed distance or more.