A display device is disclosed. The display device comprising: a display unit; a sensor unit; a storage unit; and a processor configured to: provide feedback for indicating a security on state of selected first information when selection input for selecting the first information in the security on state is detected, when a security off input for clearing security is detected in response to the feedback, obtain the fingerprint using the display unit, and convert the first information in the security on state into a security off state when the obtained fingerprint is matched with a pre-stored fingerprint, when a security maintenance input for maintaining security is detected in response to the feedback, maintain the security on state of the first information.