Science and technology innovation policies have been considered as effective policy tools in promoting regional innovation. This paper used content analysis method to analyze 321 pieces of science and technology policies published from 2006 to 2018. Structures of the policy social networks had been analyzed and discussed, and the main points and emphasis of the science and technology policy system of China’s Yangtze River Delta region had been revealed. Results indicated that Shanghai, Jiangsu, Zhejiang and Anhui’s science and technology policy system structures were relatively consistent, while the development paths were different, and the content of industrial policy of four provinces had a serious homogenization problem.