Disclosed is an optical waveguide structure capable of keeping intervals between the structure and optical elements within a certain range. When arranging a surface light emitting element and a surface light receiving element on a positioning plate provided on a substrate, elastic layers are provided between the elements and the plate. When fitting and fixing first projections of the structure in holes of the plate, second projections formed in a predetermined dimension on the structure are brought into contact with the light emitting element and the light receiving element. Therefore, intervals between lenses, and the light emitting element as well as the light receiving element are controlled within a certain range according to the dimension of the second projections. Further, stress occurring due to contact is dispersed by the elastic layers so that breakage of the light emitting element and the light receiving element can be prevented.