It is an object to provide a liquid storage bag and a liquid ejection apparatus for accurately setting the relative position between storage means of data of the liquid consumption amount, etc., and a data transfer section. A flexible bag main body 2 is provided with a liquid supply port 4, storage means 17 for storing data of the liquid type, the storage capacity, the consumption amount, etc., is provided in a part of the bag main body 2, an interface section 54 for making it possible to transfer data between a data transfer section 34 placed in a part of a case 5 or an apparatus main unit 12 and the storage means 17 is attached to a part of the bag main body 2, and position correction means 43 capable of correcting the position of the interface section 54 is provided. In doing so, the position of the interface section 54 relative to the data transfer section 34 is adjusted with the bag main body 2 housed in the case 5, and data transfer in the data transfer section 34 is established precisely.