Through technology and knowledge document analysis, companies can realise the condition of specified technology development and the potential competitors in the market. As patents provide exclusive right and legal protection for patent inventors, patents play an important role in the development of technology. This paper presents the process of patent knowledge extraction and methodologies of patent analysis to improve the efficiency of patent analysis. Furthermore, the methodologies proposed in this paper include patent map analysis, patent technology clustering, patent document clustering and technology maturity measurement. Through these methodologies, companies can gain rich information and perform better in patent management. Moreover, the strategic plans of R&D can also be determined using the methodologies proposed in this paper.