1. An apparatus for converting structured document comprising: acquisition means for acquiring distribution rule information wherein distribution rules of contents are described and receiver side situation information wherein the situations at the side of receivers of the contents are described; generation means for generating the conversion rule information wherein the conversion rules for converting structured documents in which information about the contents is described, on the basis of the distribution rule information and the receiver side situation information acquired by the acquisition means; and conversion means for converting the structured documents, on the basis of the conversion rule information generated by the generation means.