Abstract: This study systematically reviews the development trajectory of Chinas public cultural service policies, identifies their themes and evolutionary trends, extracts the underlying logic of policy optimization, and provides a scientific basis for subsequent policy formulation and implementation efforts. It select the policy texts on public cultural service issued at the central and provincial levels between 2006 and 2023 as the research corpus, and use the dynamic topic model(DTM) to conduct topic identification and evolution analysis from both thematic intensity and semantic perspectives. Visualization techniques are futher used to retrospectively trace the trends and trajectories of policy evolution, enabling the precise identification of the optimization logic for public cultural undertakings. The evolutionary analysis of the 13 policy themes identified through dynamic topic modeling reveals that the logic behind the layout of Chinas public cultural service policies follows a cyclical pattern of “constructiondeconstructionreconstruction,” exhibiting structural characteristics of diversity and balance. The framework demonstrates dual advantages of coordinated development and crosssectoral integration, achieves a dynamic equilibrium in the process of optimizing reforms and pursuing sustainable development, while demonstrating a high degree of sensitivity and adaptability to new opportunities and challenges.

Key words: Public cultural services, Policy text analysis, Dynamic topic model(DTM), Policy evolution, Topic evolution