A replaceable ink tank, removably connectable to an ink jet head body, comprises a container providing a reservoir for liquid ink to be supplied to a print head on the ink jet head body and having opposing side walls configured for guiding the side walls of the ink jet head body as the container and ink jet head body are being connected. The container includes an ink supply port positioned relative to the side walls for accepting an ink communication pipe of the ink jet head body. An engaging member on each of the container side walls engages a respective coupling member on the ink jet head body for connecting the container with the ink jet head body and holding the ink tank and the ink jet head body together with an absorbing member in the container compressed by the ink communication pipe to enable delivery of ink in said absorbing member to the ink communication pipe. Communication pipe with an ink-introducing port held in pressure abutment with the absorbing member to compress the absorbing member when the ink-jet head body is coupled to the ink storage portion. This assures a good flow of ink to the ink-jet head body.