The present invention provides a plane light source apparatus includes a light guide plate having a flat face portion and an end face portion. A plurality of point light sources are disposed in an opposing relationship to the end face portion of the light guide plate. The light guide plate mixes light from the point light sources incoming from the end face portion thereof and emit the mixed light as illumination light from the flat face portion thereof. The point light sources are a combination of point light sources having chromaticities different from each other within a predetermined standard chromaticity range, and mix light from the point light sources so that the chromaticity of the resulting illumination light fits into a target chromaticity range which is narrower than the standard chromaticity range.