small and medium-sized enterprises of science and technology are important currieries for technological innovation，and highly dependent on the policy environment. The quantitative evaluation of SME development policy effect can provide reference for the local government to support SME development in the sea-related science and technology. Based on the study of support policy to combing the domestic and foreign small and medium-sized enterprises，this paper take the policy effect of science and technology of Shandong province Qingdao City SME survey as foundation，and make an empirical investigation on policy demand and policy effect to support SME development by using the policy process theory. On this basis，this paper put forward some policy recommendations：to construct the market ecosystem for the development of enterprise in the seed stage and start-up period；to build support policy upgraded version for high growth enterprises；to support mature enterprise transformation and upgrading by adopting market-oriented means.