Though XML is widely used, it is still hard for end users to write XML documents. A lot of XML documents are data-centric documents which have formal data format. Even novices can easily write the data-centric XML documents if they use form-based GUIs. In this paper, we introduce a new method for generating form-based XML editor for data-centric XML documents automatically and an XML editor generator called XED. The DTD consists of sequence, choice, and repetition, and this structure can be represented with Document Decomposition Graph(DDG). XED allows users to generate an XML editor by applying the presentation rules to DDG. It also permits users to modify generated editor through changing editor`s GUI properties with direct manipulation.