Whether the policy implementation research of the first-generation top-down paradigm and that of the second-generation bottom-up paradigm can be synthesized and how to do so is still an academic subject of highly theoretical and practical significance. Based on critical discussions of the existing synthetic models of policy implementation research, a new multiple-system dynamic model is reconstructed. The model actually contains the basic characteristics of the main existing synthetic policy models, -- that is, it not only covers the systematicness implicit in each existing synthetic model, but also highlights the dynamic change over time in policy implementation. The advantages of the synthetic analytical model of policy implementation presented in this paper are that all factors and variables influencing policy implementation and their relations are specified, categorized and structuralized. From the diagram of such structuralized relations, it is clear to identify the logical order of the interactions between various influencing factors of different categories and their acting path on the final outcome of policy implementation.