Abstract: Voluntary blood donation serves as a crucial pillar of the public health system. Currently, China's voluntary blood donation undertaking faces dual challenges of trust crisis under pandemic impacts and utilitarian-oriented advocacy, where fluctuating donor numbers and declining public trust form a vicious cycle. International practical experience demonstrates that cultivating social altruism through cultural immersion and intergenerational education mechanisms can effectively enhance the sustainability of blood donation behaviors. With growing medical demands and heightened public health awareness, there is an urgent need to re-examine the deep structural contradictions within the voluntary blood donation ecosystem. This study systematically analyzes the trust crisis triggered by instrumental advocacy under special circumstances from the perspective of the original public welfare attributes of blood donation, combining cross-national case comparisons and empirical data analysis to propose pathways for reconstructing the public welfare ecology. The research reveals that building a sense of responsibility for the community of shared life requires breakthroughs in three key dimensions: establishing a culturally embedded intergenerational value cultivation system, creating a fully transparent institutional trust mechanism, and developing intelligent blood donation service technologies. Theoretically, it demonstrates that the paradigm shift from interest-driven to value-identified donation behavior essentially represents a collective action upgrade through the reconstruction of social psychological contracts. Practically, it verifies that blockchain-integrated traceability systems can significantly enhance donor engagement, while culturally embedded advocacy strategies effectively improve long-term donor retention rates. Fundamentally, resolving post-pandemic challenges in voluntary blood donation lies in constructing a four-in-one public welfare ecology that integrates government guidance, social collaboration, value recognition, and technological support. This approach not only aligns with the Healthy China strategic orientation but also provides innovative paradigms for global blood safety governance.

Key words: Voluntary blood donation, Altruism, Public welfare ecology, Trust crisis, Blood safety, Value identification