The present invention relates to a wavelength division multiplexing optical module in which optical signals of different wavelengths output from a single optical fibre are split and transmitted to light-receiving elements matched to various channels, and a plurality of optical signals emerging from light-emitting elements of different wavelengths are combined into one and forwarded to an optical fibre, and relates to a two-way transmission optical module which has a high optical coupling efficiency, is very precisely optically aligned by means of simple coupling, and can be inexpensively produced in large volume.
