Abstract: By using the method of input-output analysis，this paper identifies the advanced technology and core technology fields under a certain technical topic. Taking the twenty main technology fields patents of hybrid electric vehicle searched from DII from 1989 to 2013 every five years as sample data, this article applies the Python programming to patent data processing, builds patent citation matrix and estimates the technology sensitivity coefficient and technology influence coefficient, which identifies the evolution process of the advanced technologies and core technologies and reveals the development trend of the main technology fields.