Abstract: Under the background of building new infrastructure and smart city, there is no doubt that enough concern must be paid to the problem of network security. Studying the texts of China's network security policy is very necessary for recognizing the current situation of China's network security policy and promoting the construction of network security protection management system. Taking 25 national cyber security policy texts from 2015 to 2020 as samples, this paper constructs a two-dimension analysis framework of policy tools and crisis life cycle, and the texts were analyzed by quantitative method of policy content. Studies have found that China's network security policy is related to network security practice, the usage of supply-oriented policy tools is as high as 61.22%, while the internal structure of environment-oriented policy tools is obvious imbalance, with high usage of laws and regulations, but none of financial tax policy; and the use of demand-oriented policy tools is low. It is also found that policy tools focus more on the pre-crisis stage, but involve less on crisis response and post-crisis reconstruction assessment. It requires clearly understanding the relationship between cyber security policy and practical development. According to the development of cyber security, we should coordinate the application of supply-oriented, environment-oriented, and demand-oriented policy tools, attach more importance to the coordination of policy tools at all stages of the crisis life cycle, and reasonably supplement the absent policy tools to ensure China's cyber security.

Key words: Network security, Policy tools, Crisis life cycle, Policy content, Quantitative analysis