The development of strategic emerging industries means to replace the traditional technological trajectory, and its innovation process will encounter “failure” problem. Under complete market mechanism, new technological trajectory can not be automatically realized, and hence policy intervention is necessary. Based on the study of innovation policies of new energy vehicle industry, this paper puts forward: in the development of strategic emerging industries, the failure problems and its performance at different stages vary, and therefore the corresponding objectives of policy intervention and policy tools adopted should be adjusted dynamically. Besides, researching and making policies of industrial innovation should follow the theoretical framework of "stage of development-failure mechanism-policy objectives-policy tools". The reason why policy objectives of NEVI industry at different stages were not achieved includes the deviation of the focus of policy incentives, the incomprehensive policy objects, the lag of policy and so on.This study is pioneering and has important practical significance.