An apparatus for displaying a floating image is disclosed. The apparatus includes a light source that extends in a planar direction and emits light for realizing the floating image, a collecting lens, which extends parallel to the light source and refracts the light, a reflective plate, which faces the collecting lens and reflects the light that is refracted at the collective lens, and a dihedral reflector array, which extends in a planar direction and includes mirrors extending in directions intersecting each other, where a first surface of the dihedral reflector array facing the reflective plate such that the reflected light is incident on the first surface, and the reflected light is emitted from a second surface of the dihedral reflector array by being reflected by the mirrors, thereby realizing the floating image at a position spaced apart from the second surface.