When we look back to the history of Internet, we can see that the need for human being to communicate with computers through Internet has made HTML the most popular tool for application of first generation World Wide Web on Internet. This fact gives us a sense that the need for more and more computers to communicate each other through Internet will make XML the mostly used technology for computers on Internet to exchange and store distribute data in near future. But even with the help of DTD and schema to today's XML documents & data sources, the programming works for programmers to integrate XML documents through Internet is still very hard and complex. One of the important reasons to this situation is that the programmers who want to integrate the XML documents have not only to analyze the document's original DTD, but also to write a new DTD for the new integrated XML data. Because DTD is really a specification for one XML document, it is only suitable for software & programs that have basic knowledge of DTD to analyze and create them. Based on the character of XML documents and their DTD specifications, this paper proposed a new system framework to use software agent to help the work for XML document & data integration. While software agents have DTD knowledge for them to automatically analyze and memorize the character of XML's DTD, they are absolutely effective in works of DTD analysis and XML creation. This character makes the system with the framework of this paper efficiently relieve the programmers' work by the automatic processing in XML document’s integration.