Objective: In centralized procurement of medical consumables, two models coexist: centralized volume-based procurement and volume-based price linkage, yet their intrinsic logic and synergistic mechanisms lack systematic research. This paper aims to reveal the “source-flow” hierarchical relationship between the two models and to provide a reference for optimizing procurement strategies. Methods: Six procurement cases guided by Guangdong Province and led by Shenzhen City from 2021 to 2025 were selected, and the two models were systematically compared across nine dimensions. Results: Centralized volume-based procurement generates groundbreaking new benchmark prices through competition (setting the benchmark); volume-price linkage relies on selected prices from other provinces to achieve regional coordination (promoting the benchmark). The two models present a clear “source-flow” hierarchical relationship: centralized volume-based procurement is the “source” of the “volume-for-price” system, while volume-price linkage serves as the extension and amplification of this outcome. Conclusion: The “precision matching plus synergistic linkage” mechanism explored in Shenzhen establishes a two-level decision-making system using out-of-province centralized procurement as a pre-condition, moving from setting the benchmark to promoting the benchmark, while balancing cost control, implementation efficiency, and supply stability, which can provide a reference for other regions.