Abstract: Based on existing researches on diffusion of innovation， policy diffusion and policy pilot， this paper attempts to build an analytical framework， including innovation attributes， participants and upward paths， and analyze different antecedent conditions and mechanism paths that affect the transmission of policy innovation by the use of multiple-case qualitative comparative analysis and semi-structured interview. It is found that the bottom-up policy innovation transmission can be divided into top-level driving type， development leading type， business innovation type and grass-roots demand type. The effectiveness， the demand and the compliance of policy innovation are the fundamental factors which affect transmission of policy innovation. Decision-making entities and business entities are necessary participants to any type of policy innovation transmission. The vertical path is the main path to make policy innovation transmission come true， and cross sector path can also realize the vertical transmission of policy innovation under specific policy circumstances.

Key words: grassroots innovation; national policy; policy innovation; innovation transmission; policy diffusion