Since its implementation in 2013, the Teamcenter design information management system has served as a comprehensive design management platform for the Nuclear Engineering Research and Design Institute. Over the years, this platform has significantly enhanced the informatization and digitalization of China's third-generation nuclear power design, equipment manufacturing, and engineering construction. It ensures the advancement, safety, and economic efficiency of the Hualong One project. Nuclear power design and information technology are deeply integrated, allowing various departments to accumulate extensive experience in adapting the platform to suit the business processes, rules, and data of engineering management. However, there is a recognized need for improvements in design management and platform optimization. This paper proposes the establishment of a "design management platform maturity evaluation system" to assess the platform's effectiveness and visualize evaluation data. Through the definition of evaluation indicators and the establishment of an Analytic Hierarchy Process (AHP) table, this study develops a maturity evaluation system for the design management platform. It analyzes key platform elements via expert scoring to perform the maturity assessment. Subsequent improvements are applied in the CIMS3.0 system, enhancing the safety, efficiency, and convenience of data querying and statistical analysis. This includes features such as quick access to statistical reports and comprehensive data queries, thereby improving the quality and efficiency of design management.