An spatial image display apparatus includes: a first optical plate that transmits an incident light beam such that transmission gain reaches a peak greater than 1 in an optical axis direction of the incident light beam; and a second optical plate in which a plurality of optical elements are provided in a matrix formation, which regularly reflect a Z axis-direction component of a transmissive light beam of the first optical plate and are retroreflective with X and Y axes-direction components of the transmissive light beam, in a substrate having a normal line in a Z axial direction.