Abstract: A cartridge for inkjet printer includes housing and an ink storage tank defined inside the housing. An ink outlet is defined in the bottom portion of the housing, while an air inlet and ink inlet are formed on the top portion of the housing. All of the ink outlet, air inlet and ink inlet are communicated with the ink storage tank. A filtration chamber is defined in the ink storage tank. A filtration core is provided in the filtration chamber. The chamber is communicated with a flow guiding slot disposed at one side of the ink storage tank through a filtration hole. The other end of the flow guiding slot is communicated with the ink outlet. Advantageously, bubbles genreated during operation of the cartridge can be stored in the bubble chamber of the housing, thus eliminating bad effect of the bubbles on the normal flow of the ink out of the ink outlet.