Optical module and assembly method thereof

An optical module includes: an optical assembly, including a light receiving assembly and/or a light transmitting assembly; a printed circuit board, on which the optical assembly is mounted; an adapter, used for docking with external connectors, wherein the adapter is configured to fit the optical assembly and to be fixed to the printed circuit board, and the adapter includes a metal part and a plastic part; and a conductive shell, used for accommodating the printed circuit board, the optical assembly, and the adapter, the conductive shell being electrically connected to the metal part of the adapter.