】Campus networking and education informationization have become the main direction of education development in our country at the present stage. And campus network has become an indispensable tool for teachers and students in their daily life, management and scientific research activities, playing an increasingly important role in colleges and universities. From the construction of campus network security defense system, the specific implementation, and the safety problems in the application layer and management layer, this paper explores on the construction and implementation of the campus network security defense system.