As the access control mode of notepad files cannot meet the requirements of risk control for sensitive file hierarchical access, this paper proposes an application classification-based detection method for abnormal access to sensitive files. The application classification and file classification, access control policy mapping, and basic and preset policy detection are designed. Combining the operating system’s identification control of different applications at runtime, we monitor the abnormal access of sensitive files by hierarchical applications. The cross-access experiment of different levels of application to different sensitive files verified the effectiveness and security of hierarchical access control strategy and sensitive file abnormal access detection and reduced the risk of disclosure of sensitive files.