A liquid container for containing printing liquid for supplying to a recording head for an ink jet recording apparatus, the container includes a first chamber containing a negative pressure producing material and having a printing liquid supply port connectable to a recording head for allowing printing liquid to be supplied to the recording head and an air vent for allowing ambient air to enter the container, and a second chamber which provides a printing liquid reservoir for the first chamber and is substantially closed apart from a communication port communicating with the first chamber to allow the printing liquid to flow into the first chamber and to allow air to be introduced into the second chamber from the first chamber. The second chamber comprises a replaceable printing liquid chamber.