When　enterprises　were　engaged　in　completely　different　technological　field,　the　patent　data　for　the　comparisons　of　enterprises　technological　innovation　capability　is　not　appropriate.　The　paper　propose　a　statistical　method　for　patent　based　oil　hierarchical　clustering　analysis,　which　help　to　explore　the　structural　characteristics　of　distribution　in　the　technological　areas,　cluster　analysis　was　employed　to　group　the　firms　into　homogeneous　categories.　With　identifying　groups　and　members　of　the　group,　judge　enterprises　by　their　focus　of　R&D　activity　and　the　width　of　the　technological　areas.　The　paper　used　the　data　of　patent　in　ICT　an　example　for　the　empirical　analysis.