Abstract. We propose a descriptive high-level language XDTrans devoted to specify transformations over XML data. The language is based on unranked tree automata approach. In contrast to W3C’s XQuery or XSLT which require programming skills, our approach uses high-level ions reflecting intuitive understanding of tree oriented nature of XML data. XDTrans specifies transformations by means of rules which involve XPath expressions, node variables and non-terminal symbols denoting fragments of a constructed result. We propose syntax and semantics for the language as well as algorithms translating a class of transformations into XSLT.