A display device and a display method using the same are disclosed. The display device includes: a display panel including a first substrate, a second substrate and a liquid crystal prism arranged between the first substrate and the second substrate; and a backlight source configured to emit a light which is incident onto the second substrate at an oblique angle; wherein the liquid crystal prism is configured to adjust a deflection angle of the light emitted from the backlight source traveling between the first substrate and the second substrate such that the light emitted from the backlight source is totally-reflected at a light exit face of the display device or exits from the light exit face of the display device.