As a demonstration zone for common prosperity, Zhejiang Province regards the sinking of higher vocational resources into counties as a key measure to address the “county-level talent shortage” and “urban-rural educational gap”. Based on resource dependence theory and collaborative governance theory, this study adopts a mixed research method of “policy text analysis + survey of 88 county-level industrial colleges + in-depth interviews with 6 typical cases”. It systematically sorts out the threefold dynamic mechanism of “policy-driven, market-oriented, and university-local symbiosis” for the sinking of higher vocational resources in Zhejiang, and refines three core models: “university-county symbiosis type”, “industrial cluster embedded type”, and “mountain-sea cooperation empowerment type”. By constructing a four-dimensional performance system of “resource supply - talent training - industrial service - common prosperity”, combined with the 2025 monitoring data from the Zhejiang Provincial Department of Education, the results show that the sinking practice has increased the proportion of “double-qualified” teachers in county-level secondary vocational schools by 30 percentage points, the local employment rate of graduates has reached 42%, and more than 2,300 technical problems have been solved for enterprises. The study finds that there are dilemmas such as unbalanced regional sinking, weakened collaborative mechanisms, and biased evaluation orientation in practice. Accordingly, it proposes a three-dimensional breakthrough path of “digital empowerment for balanced allocation”, “interest linkage to strengthen collaboration”, and “differentiated evaluation to guide quality”, providing a “Zhejiang plan” for vocational education empowering county development under the background of common prosperity.