An optical switching device of which cost and size are smaller than the conventional is provided. In the optical switching device, a spectroscopy section in each of optical switches disposed being piled up to plural layers is integrally formed. And there are provided with a first light control element integrally formed on paths of light beams, which are outputted from each of the first ports in each of the optical switches disposed being piled up to plural layers and propagate in space, a second light control element integrally formed on paths of the light beams, which are outputted from the spectroscopy section and propagate in space, and a third light control element formed integrally with each of second ports at a position corresponding to the reflection direction by reflector on paths of the reflected beams passed through the spectroscopy section in each of the optical switches.