A display element includes a light source, an optical waveguide, a light-extracting portion. The optical waveguide has two ends and a side surface. One of the two ends is near the light source. The other of the two ends is far from the light source. The side surface extends from the one end to the other end. The light-extracting portion is provided near the side surface to extract light out of the optical waveguide. In addition, the other end changes a light path of forth-traveling light so that an incident angle of back-traveling light is smaller than the incident angle of the forth-traveling light.