PURPOSE: To allow the optical waveguide and the optical fiber to be subjected to optical coupling in the lump and with high accuracy even if they are plural, respectively, so that as for the optical waveguide, its core layer only is subjected to film thickness control with high accuracy in order to secure the alignment of high accuracy in the height direction.

CONSTITUTION: An optical fiber 14 is fixed to an optical fiber fixing groove 20 formed on the substrate surface 19a of an optical fiber fixing substrate 19 so that a distance extending from its optical axis center to the substrate surface 19a becomes equal to a distance extending from the upper face of an optical waveguide 12 to the center of an optical waveguide core 15, and in the optical fiber fixing substrate 19, two alignment projections 18 are formed on both sides of the optical fiber fixing groove 20, and on an optical waveguide substrate 11, an alignment guide 13 having the guide face 13a and a guide groove 13b of the same height as the upper face of the optical waveguide 12 is formed, and in a state that the tip of the optical fiber 14 and the tip of the optical waveguide 12 are brought into contact closely with each other, two alignment projections 18 are inserted into the guide groove 13b, and the substrate surface 19a is allowed to adhere closely and fixed to the guide face 13a.