To support the realisation of semantic web – as well as digital library, the semantic information content of web documents need to be specified in order to make the tangled information more accessible to search engines and other applications. A number of efforts to support the semantic representation of web documents have been proposed. One such effort is the semantic document modelling of which existing web documents are classified and organised to form a semantic document model representing the contents of respective web documents. In this paper we propose a tool meant to assist in constructing semantic document models using natural language analysis technique and a domain specific ontology. Together with users involvement and participation the tool gradually construct the semantic document model which is represented as XML.