Aiming at the defects of CERNET in network planning, construction and management, this paper analyzes the main factors of network security management, network security management maturity gradient model division, and puts forward the maturity of the five levels-five gradient matrix, which constructs a network security management maturity model. This model can not only detect the security vulnerabilities in the management of CERNET network, but also improve the safety management level, which is proved by the analysis of defects from Sichuan Vocational College of Information Technology campus network security management with the model, the results of which show that the Academy reaches maturity specification level.