To solve the following problem; a conventional optical filter module is configured so that a beam of light is made slantingly incident to an optical filter unit, and a refractive angle of the incident beam of light is different by wavelengths, thereby making adjustment at the time of manufacturing the optical filter module difficult.

The optical filter unit 30 which constitutes the optical filter module 100 is provided with a 1st plane 3 to/from which two or more beams of light 11 of different wavelngth bands are made incident or reflected, a 2nd plane 2 to/from which a single beam of light 12 including two or more wavelength bands is made incident or reflected, and a filter part which multiplexes the two or more beams of light 11 of the different wavelength bands into a single beam of light including the two or more wavelength bands, or demultiplexes the single beam of light 12 including the two or more wavelength bands into the two or more beams of light 11 of the different wavelength bands, and all the two or more beams of light 11 of the different wavelength bands are made incient or reflected almost vertically to/from the 1st plane 3 from different positions 24, 25, 26 on the same 1st plane 3, and the single beam of light 12 including the two or more wavelength bands is made incident or reflected to/from the 2nd plane 2 almost vertically to the 2nd plane 2.