The invention provides a display device and a working method thereof. The display device includes multiple functional film layers which are stacked and a self-destructive mechanism. The self-destructive mechanism is located in the multiple functional film layers and includes a shell and a self-destructive medium stored in the shell, and when the shell is damaged, the self-destructive medium is leaked out from the shell and destroys the functional film layer making contact with the shell. The provided display device and the working method thereof can achieve the effect of confidentiality of thesecret design inside the display device.