A self-setting security guarding system and method for protecting against unauthorized access to data stored in a data processing apparatus, comprising setting various items used to guard data, wherein the items consist of protected areas with access control for data storage and access therein, authorized types of files with access controls, and access rules of safety regulations enabling the data processing apparatus to verify access to data contents stored therein or in the protected area thereof; and detecting access events of the protected area or types of files using the access control and generating a request for analysis when an access event is detected, and further analyzing whether the detected access event complies with the access rules and the analysis request to permit or deny execution of said access event depending on whether it complies or not with safety regulations.