Abstract: A document storage apparatus of a document reading system. The document storage apparatus has a document storage section which stores a document created by a document creating apparatus and having a plurality of pages by forming the document into an electronic document in which at least one set of image data is stored in page units. When a read demand has been issued from a document reading apparatus, a read demand receiving and analyzing section receives the read demand to analyze the required contents. The required electronic document is, in page units, acquired from the document storage section so as to be processed into a format meeting the required contents by a document processing section. Then, a response data generating section generates response data in which reference information with which page instruction is enabled when a next read demand is issued is embedded. The response data formed in page units is transmitted to a document reading apparatus by a document transmitting section.