Disclosed is manufacturing method of an optical module including an optical/electrical converter, a receptacle, and a substrate, the method including: the receptacle that has a guide portion that aligns an optical connector ferrule that holds an end portion of an optical fiber and that has a device accommodating portion that matches with a profile of the optical/electrical converter; a process of accommodating the optical/electrical converter in the device accommodating portion; a process of securing the optical/electrical converter to the receptacle; and a process of electrically connecting to the substrate that electrically connects to the optical/electrical converter the optical/electrical converter secured to the receptacle.