An optical waveguide device for loss absorption, and a fabrication method thereof, are provided. The optical waveguide device for loss absorption includes: a substrate of a predetermined material; a lower cladding formed on the substrate; an optical waveguide formed on the lower cladding, and formed of a material having a refractive index greater than a refractive index of the lower cladding; an upper cladding formed so as to completely cover the optical waveguide; and an absorption layer formed of a material having refractive index greater than a refractive index of the upper cladding, and formed on the upper cladding to a thickness which can absorb a reflected or radiated optical signal. As described above, an absorption layer capable of absorbing light is formed in the waveguide device upon fabricating the optical waveguide, thus minimizing or removing loss due to reflection and radiation of an optical signal.