An ink container (1, 51) has an ink-holding space (9a, 89) maintained at substantially constant negative pressure until the ink contained in the ink-holding space (9a, 89) has been exhausted. The ink container (1, 51) includes a flexible wall (3, 55) and an urging member (5, 59, 76). The flexible wall (3, 55) forms a part of the ink-holding space (9a, 89) and the outer surface of the flexible wall (3, 55) is exposed to the atmospheric pressure. The urging member (5, 59, 76) takes the form of, for example, a spring. The urging member (5, 59, 76) is incorporated in the ink-holding space (9a, 89) and urges the flexible wall (3, 55) outwardly of the ink-holding space (9a, 89). The atmospheric pressure is exerted on the flexible wall (3, 55) so that the flexible wall (3, 55) is displaceable inwardly of the ink-holding space (9a, 89) as the ink is supplied from the ink-holding space (9a, 89) to an external device. The urging member (5, 59, 76) operates substantially in a plastic deformation region thereof.