An optical element includes a light guide is provided with a incidence section and a emission section, a semitransmissive reflective film is provided in the inside of the light guide, a first diffraction element is provided in the incidence section, and is provided with a plurality of gratings, a second diffraction element is provided in the emission section, and is provided with a plurality of gratings, and a reflective film is provided in the incidence section in a periphery of the first diffraction element, in which the pitch of the plurality of gratings of the first diffraction element is equivalent to the pitch of the plurality of gratings of the second diffraction element, and each extension direction of the plurality of gratings of the first diffraction element is the same direction as each extension direction of the plurality of gratings of the second diffraction element.