Abstract: A light guide system includes a transparent light guide portion that guides light beams incident from one end side to a light-emitting portion. The light guide portion includes a plurality of partial reflection surfaces that are disposed between a first surface and a second surface which are parallel to each other and are inclined at the same angle such that a first end portion is positioned closer to the one end side than a second end portion is. Intervals between the partial reflection surfaces in a first direction are widened from the one end side toward another end side. In a state where the light guide portion is disposed in front of an eye of an observer, the light guide portion is inclined such that the another end side is further away from a face of the observer than the one end side is.