Abstract. Objective: to improve the network security management. Method: using multi dimension extension fuzzy technology. Process: build a multi dimensional model to comprehensive evaluation of network security management level. From network security management systems, human input, technology effect three aspects, comprehensive evaluation of network security management level. The weights of the various indicators and the evaluation values of each dimension are obtained by the analysis of Extension Association. Results and analysis: The application shows that the model can be integrated with the factors of management, technology, manpower, etc. has a significant effect on the improvement of network security management. Conclusion: in this paper, the use of multi dimensional extension based fuzzy technology is helpful to improve the network security management.