1. A document delivery device which delivers a structured document necessary for a predetermined processing to an application program which executes the predetermined processing on the structured document, comprising: reception means for receiving a delivery request from the application program; specification means for separately specifying structure information and contents of a structured document to be delivered, based on the delivery request received by the reception means; generation means for obtaining the structure information or the contents from a predetermined storage unit and generating the structured document to be delivered, based on specification from the specification means; and delivery means for delivering the structured document generated by the generation means to the application program.