A user terminal and a display device thereof are provided. The display device includes a display panel including a glass plate for displaying an image by outputting light, and a polarizing plate attached to both a top surface and a bottom surface of the glass plate for exposing an edge portion of the glass plate, a cover window mounted on the display panel for transmitting the light, an adhesive sheet interposed between the display panel and the cover window and for adhering the cover window at the edge portion of the glass plate. The user terminal can be formed to have a small thickness and size, and light is shielded from being leaked to the outside of the user terminal via an edge portion of the display panel in the user terminal.