Abstract: A replaceable ink reservoir adapted to an inkjet print system is provided. Since the inkjet print system of the conventional arts drives an air pump to inject air into the ink reservoir to discharge the ink stored in the ink storage pack to a printer cartridge, serious noise may be generated when the air pump is driven. In addition, in order to discharge the ink through the injection of the air, the ink reservoir should be one integrated body having a hermetically sealed structure, therefore, a user cannot visually check an ink storage level in the ink storage pack from the exterior of the ink reservoir. Further, since a nozzle connecting pipe is always connected to an ink outlet port connected to a front end of the ink storage pack, it is difficult to uniformly maintain discharge pressure of the ink, thereby causing an error image to be formed on a recording medium.