A display device, including a first polarizing film, a pixel array module, a second polarizing film, and a first electronically controlled phase retardation module, is provided. The pixel array module is disposed in overlap with the first polarizing film. The second polarizing film is disposed in overlap with the pixel array module. The first electronically controlled phase retardation module includes a first liquid crystal layer, two first alignment layers, and two first conductive layers. The first liquid crystal layer and the first alignment layers are disposed between the first conductive layers. The second polarizing film is located between the pixel array module and the first electronically controlled phase retardation module. One of the first polarizing film and the second polarizing film directly contacts one of the first conductive layers of the first electronically controlled phase retardation module. The display device has a switchable viewing angle and is thinner and lighter.