A flat panel display device includes a display panel, a backlight module, a printed circuit board and a protection structure. The backlight module is disposed on a non-display side of the display panel. The printed circuit board with a signal connector is connected with the display panel and disposed between the display panel and the printed circuit board. The protection structure is used to protect the backlight module from the deformation caused by the external force, especially the optically films in it, like conductive film etc. The protection structure includes a protective film, a movable piece and an elastic element. The protective film is covered on the printed circuit board and having an opening to expose the signal connector. The movable piece is connected with the protective film, and the opening is disposed between the movable piece and the protective film.