The invention provides a submerged arc welding process for a marine engineering structure under low-temperature environment service. The method comprises the following steps: (I) determining a welding way for a base material; (II) determining the joint type of the base material; (III) selecting a welding material; (IV) determining welding parameters; (V) performing welding control. The welding process of an EH36-Z35 steel plate/tube of which the thickness is 40-88 millimeters under low temperature environment service is implemented. Meanwhile, the welding process of a DH36-Z35 steel plate/tube of which the thickness is 45 110 millimeters under low temperature environment service is implemented. By adopting the process, a large amount of labor force and electric power are saved while a thermal treatment process is replaced, the equipment investment is reduced, the working period is shortened, and the degradation of the mechanical property of a welding joint caused by thermal treatment faults is avoided.