An optical transmitting and/or receiving module comprises an optical plug comprising a housing which is provided with at least one ferrule assembly having an optical fiber therein, a main receptacle body connected to the optical plug, and an optical link assembly comprising a substrate. The substrate has at least one optical semiconductor element and circuit elements for signal processing fixed thereon. The optical link assembly is fixed to the main receptacle body so that the at least one optical semiconductor element opposes a tip end of the optical fiber of the optical plug and a surface of the substrate is perpendicular to an optical axis of the optical fiber.
