The invention discloses a coating process for applying water paint to an elevator door and door pocket sheet metal parts. The process sequentially comprises the following steps: firstly, pretreatment is carried out, wherein the surface of the elevator door and the surfaces of the door pocket sheet metal parts are sequentially subject to pre-degreasing, degreasing, primary washing, surface conditioning, phosphorization and secondary washing, a uniform gray phosphating film not prone to rusting is generated on the surface of a workpiece, and then an electrophoretic primer coating system is used for conducting operation; secondly, anticorrosive primer is applied in an electrophoretic painting manner; thirdly, a high-pressure electrostatic spraying manner is adopted to spray water-based top-coat or water-based top-coat and water-based finishing paint. According to the process, the water paint can be effectively applied to coating of the elevator door and the door pocket sheet metal parts, the environmental harm and potential safety hazard, caused by the traditional coating process, of the elevator door and the door pocket sheet metal parts can be solved, meanwhile, same-line production of electrophoretic primer and water-based top-coat can be achieved, high automation of coating production can be achieved, the coating process is environment-friendly, and the coating product quality and the production efficiency can be obviously improved.