The invention discloses a big data analysis method applied to the field of information security, and belongs to the technical field of information security. The big data analysis method comprises thefollowing steps: S1, establishing a network security database; S2, analyzing network data; S3, carrying out safety management of the data; S4, constructing a safety early warning; and S5, performing alarm processing. The big data analysis method detects whether a security threat occurs in network data analysis by establishing a big data analysis model, wherein the big data analysis model is used for preprocessing acquired data, reorganizing the original data and forming a basic data relation graph through feature extraction and data fusion modes, constructing an attack tree model through the data relation graph so as to speculate the attack behavior of the next step, combining the data statistical characteristics in the attack, designing the data analysis process, method and rule, and deeply mining the preprocessed data by applying the real-time analysis and offline analysis modes, so that the hidden danger information in the data can be detected more quickly, and the security detection efficiency is improved.