The goal of building Guangzhou into an international scientific and technological innovation city has evolved several times，and the policy system is large in scale and complex in structure. This paper abstracts the current policy clusters and projects from the 13th Five-Year Plan of science and technology innovation，introduces the theory and technology of policy performance evaluation，constructs an evaluation index system corresponding to the specific policy projects and policy system，and carries out an empirical evaluation by selecting 45 policy project samples according to the scientific principles. The result shows that the comprehensive performance of the policy system is good，in which the performance of policy preparation and policy process are better than the policy result. After the implementation of the policy，the gap between Guangzhou and other innovative cities in the country at the highest level has narrowed significantly in recent years，but the gap between Guangzhou and the innovative cities of international advanced level is still large. The disadvantages of policy implementation were concentrated on innovation input，innovation ability construction，resource structure and incubator service. Therefore，efforts should be made in terms of adjusting the way of support for scientific and technological innovation，continuously optimizing innovation space，consolidating scientific and technological cooperation mechanism between Guangzhou and Hong Kong，and attaching great importance to attracting talents，so as to improve the policy and promote the scientific and technological innovation strength and international influence of Guangzhou.