An ink container which includes an ink supply port for supplying ink to a recording head, and is formed with a flexible member shaped like a bag, which deforms in accordance with an amount of remaining ink contained therein, the ink container including: a sensor module serving as vibration activating and detecting unit, provided on one of the surfaces of the ink container, for emitting a vibration to the ink; and a rigid member provided on a location of the other surface of the ink container, which is opposed to the sensor module; wherein an amount of remaining ink is detected based on a vibration characteristic of the vibration activating and detecting unit which depends on a distance between the vibration activating and detecting unit and the rigid member.