A method of manufacturing an optical module including a transparent substrate having an electro optical element on one surface side, an optical transmission line support member, which is arranged on the other surface side of the transparent substrate and supports one end of an optical transmission line, and an optical coupling member, which is arranged on the other side surface of the transparent substrate and has a role of optical coupling the electro optical element with the optical transmission line, wherein the method of manufacturing the optical module comprising the steps of:
- forming a guide pin in either the optical transmission line support member or the optical coupling member;
- forming a guide hole, in which the guide pin is to be inserted, in the other one of the optical transmission line support member and the optical coupling member, in which the guide pin is not formed, such that the diameter of the guide hole is made larger to produce a gap between the guide pin and the guide hole when the guide pin is inserted into the guide hole;
- mounting the optical transmission line support member on the transparent substrate such that the guide pin is being inserted into the guide hole;
- filling up the gap between the guide pin and the guide hole with a filler material, which is cured by carrying out a predetermined processing;
- adjusting a position of the optical transmission line support member within a range in which the guide pin is movable inside the guide hole;
- and
- curing the filler material by carrying out the predetermined processing to the filler material, which is filled up in the gap between the guide pin and the guide hole.