Abstract: A device for refilling a print cartridge (100) of an ink jet printer comprising a receptacle (4) with a sealing element (7), in which the print cartridge (100) can be seated with close tolerance. The sealing element (7) is positioned against the ink nozzle (103) provided on the underside of the housing (101) and is brought into tight sealing engagement by means of a locking element (5) which engages with an edge of the casing of the print cartridge (100). In addition, a hollow needle carrier (18) with a hollow needle (17) is provided, which can be seated upon the print cartridge (100) or as the case may be, the receptacle (4). The hollow needle (17) penetrates through a bore hole (106) of the print cartridge (100) into the ink supply chamber on the inside of the print cartridge (100). A refill cartridge (200) can be stuck onto the hollow needle (17). With the help of this device, print cartridges can simply and safely be refilled.