Abstract
With the widespread diffusion of semi-structured data in XML format, algorithms for mining information from XML documents are becoming increasingly important. So a similarity function is the key of a successful XML data management process. In this paper, we propose a new method to measure the similarity between XML documents by considering their structures and contents, which comprises three layer matching: element matching, path matching and document matching. The similarity of document's structure is found by partial matching technique and that of document's contents is found by taking into account of the syntactic information, semantic information and position of elements.