Abstract: There is no paradigm of policy strategic environmental assessment (SEA) commonly agreed in China. The relevant definitions of policies were sorted out into broad sense, narrow sense and policy instruments. Policies in a narrow sense should be the object of policy SEA. The practice of policy analysis should not only emphasize on policy coordination of policy instruments in the policy system consisting of policies in a broad sense, but also analyze the relationship between the policy and other policies from the perspective of relevant policy tools in the policy system to form a policy synergy. The paradigm of policy SEA, covering the levels of "value norm-disciplinary substrate and evaluation model- institutional arrangement", was proposed, and was preliminarily applied with a renewable energy policy of one province as an example. Suggestions included strengthening theoretical research on policy SEA, accumulating practical experience, promoting institutional construction, and finally establishing the paradigm of policy SEA.