At present, the exchange of information via Internet is widely used in electronic government (e-Government). To securely and effectively exchange offi¬cial documents among government agencies, an exchange model has been devel¬oped by the government of Taiwan. Although a RSA cryptosystem is used in the model to ensure security and XML is employed to increase interoperability, the cur¬rent design does not take advantage of the rich structure of the XML documents, and it may result in possible security leaks due to the fact that, traditionally, the whole document is signed and encrypted. Considering the characteristic that it is easy to integrate encryption, signature and access control into XML documents, a fine-grained official document exchange model for e-Government is proposed in this article. In addition, the proposed model conforms to standards such as XML Encryption and XML Signature.