An inkjet printer, which comprises a slide lid slideably connected with the cartridge body, wherein a fixed clamp is formed on both sides of the cartridge body respectively; a movable wall which is engaged and fastened with the fixed clamp at the end is formed on both sides of the slide lid respectively; and a friction force generating component is arranged on one side of the movable wall. Due to the friction forces generated by the friction force generating components, two sidewalls of the movable walls are tightly engaged with the inner wall of the ink cartridge bin of the printer to lock the ink cartridge and fix the ink cartridge into the ink cartridge bin of the printer. The technical problems of poor contact of a chip and abnormal disengagement of an ink container as locking members are loosened when the ink cartridge on the printer can be solved.