Against the backdrop of promoting high-quality development as outlined in the Outline of the 15th Five-Year Plan for National Economic and Social Development of the People’s Republic of China (hereinafter referred to as the “15th Five-Year Plan”), the high-quality development of science popularization initiatives depends on effective supply and rational allocation of science communication resources. However, the construction of science communication resources in China has long faced challenges such as insufficient coordination among stakeholders, fragmented resources, and a lack of sharing mechanisms. Breaking free from the current difficulties in jointly building and sharing science communication resources has thus become an urgent research topic. This study takes policy documents on science communication and public engagement from the United States and the United Kingdom as its research subjects, employs policy text analysis methods, systematically reviews 43 policy documents issued between 2014 and 2025, and through three-level coding identifies 30 initial categories and 7 main categories. It constructs a “reservoir” analytical framework comprising five core components: input layer, storage layer, processing layer, output layer of benefits, and monitoring mechanism. The study finds that both countries have established input mechanisms featuring multi-stakeholder collaborative investment in science communication and public engagement; resource integration mechanisms centered on strategic planning, coordination mechanisms, and platform development; processing mechanisms driven by collaboration, openness, digitalization, and industrialization; and monitoring and evaluation mechanisms including policy oversight and public supervision. Based on this foundation and in light of the practical needs for co-construction and sharing of science communication resources in China, recommendations are proposed from four dimensions: investment models, integration capacity, operational mechanisms, and monitoring and incentives. First, establish a dual-track investment model combining “public welfare” and “market” approaches—using public welfare funding to ensure accessibility and equity in science communication, while leveraging market-based investments to activate social capital participation. Second, strengthen the capacity for integrating science communication resources through strategic planning, coordination mechanisms, and platform development. Third, build an efficient and collaborative operational mechanism for co-construction and sharing of science communication resources. Fourth, develop a scientific monitoring system for science communication resources and improve incentive mechanisms related to these resources.