The invention discloses a gas-shielded flux-cored wire for welding of a SUS316L austenitic stainless steel deep-cooling low-temperature storage and transportation container and device and the preparation method thereof. The as-shielded flux-cored wire comprises a steel strip and a flux core wrapped in the steel strip, and the flux core comprises the following components of, by weight, 4.25-5.85 parts of natural rutile, 0.8-1.9 parts of quartz sand, 0.7-1.8 parts of sodium titanate, 0.25-0.3 part of sodium fluoride, 0.125-0.275 part of calcined alpha alumina, 0. 27wt% of calcined alpha aluminaand 0.025-0.15 part of nitrogen-containing ferrochromium, 0.085-0.05 part of spray silicon iron, 1.05-1.45 parts of electrolytic manganese, 3.6-4.85 parts of metal chromium, 6.42-6.85 parts of atomized iron powder, 1. 9-2.5 parts of nickel powder, and 1.0-1.35 parts of molybdenum. The gas-shielded flux-cored wire has the advantages that efficient semi-automatic and automatic welding technologies are achieved, the welding efficiency is high, splashing is low, the appearance is attractive, the welding current is wide, and the voltage adaptability strong.