The technique of collaborative design and manufacture is not only very important, but also urgent necessary for space antenna. Building on unicode, XML provides the standard format describing data in various types, so it has the virtue of integrating heterogeneous databases. In this paper, the elementary research has been done on XML-based integrating technique for heterogeneous databases of space antenna. Firstly, the overall flow for collaborative design and manufacture of space antenna shows that five databases should be integrated. Secondly, a XML-based integration system frame is conceived for space antenna databases. Thirdly, an effective XML-based transformation mechanism is proposed for the data integration process between relational database and document-based database. Finally, the implement of XML-based database integration is demonstrated in a space antenna design.