Abstract: Information resources have increasingly become important production factors and social wealth. Governments at all levels have formulated relevant policies in line with the trend of the times and made efforts to promote the opening of public information resources in key areas. Exploration of the change of public information resources open policy is of great significance for future policy formulation. This article obtained 467 public information resources open policies at the national level in China. Based on the position of the words in the text, the subject words of the policy text are obtained, and the subject words are weighted twice according to the policy type. Using the method of co-word & clustering, the focal points for the formulation of public information resources open policies in each period are obtained to explore the law of policy changes. The study found that there are eleven policy themes in four periods of the opening public information resources, forming three distinct groups, that is, government information public sharing, construction and maintenance, value-added utilization; each group showed different transition patterns. In the whole process of the opening public information resources, there has been no faultage in policy themes, while it showed a gradual integration and deepening trend.

Key words: Open public information resources, Policy change, Information policy, Co-word analysis, Government information disclosure, Information value-added usage