A photoelectric coupling assembly and manufacturing method thereof enabling a three dimensional electrical wiring pattern is provided. The assembly includes a photoelectric conversion unit equipped with a photoelectric conversion element and a molded article. The molded article has a hole configured and arranged to have an optical fiber inserted there-through such that a distal end of the fiber faces an active layer of the conversion element, a front surface on which the conversion unit is mounted, and a side surface being contiguous to the front surface. The lead being insert molded into the molded article has a first surface being exposed at the front surface and electrically connected to the conversion element, a second surface being exposed at the side surface, and an engaging portion having a width increasing in a direction away from the front surface. At least a portion of the engaging portion is contained inside the resin forming the molded article.