Through mathematical analysis, the primary components analysis (PCA) is used to analyze the effect of influential factors on campus network security (CNS). Based on PCA model and, the results are computed. Through case study, it can be seen that some factors and characteristics play very important role in influencing CNS and all factors should be considered because the effect depends on the factors interaction. Through analysis and discussion, it is concluded that, under the premise of minimizing the information loss, the application of PCA in analyzing effect on CNS is approved to be practicable and applicable.