A pixel unit and a display device are proposed. The pixel unit includes a primary subpixel, a white subpixel, a display data line, a display scanning line, a common line and a mode scanning line. When the display device is in a 2D display mode, the white subpixel appears bright under the control of the display mode signal. Ehen the display device is in a 3D display mode, the white subpixel appears dark under the control of the display mode signal. Owing to the design of the present invention, power which the convention pixel and display device consumes is obviously reduced. Besides, crosstalk occurring in the conventional display device is successfully solved.