Abstract: The cold spraying technology was used to prepare pure Al coating on the upper surface of 7050 aluminum alloy friction stir welding(FSW) joint. The effect of cold spraying on the improvement of the stress corrosion resistance of FSW joints was studied, and the improvement factors were explored. The results show that the stress corrosion resistance of cold sprayed FSW joints has been significantly improved, the stress corrosion fracture time has been extended from 24 h to more than 480 h, and the fracture location changes from the heat-affected zone on the advance side to the weld nugget zone.The pure Al coating has a deposition thickness of about 500 μm and a low porosity of only 0.74%. It is evenly distributed on the upper surface of the joint without oxidation and powder particle accumulation. It can provide better physical protection for the joint in a seawater corrosive environment, which can effective improve the stress corrosion sensitivity of joints and the promotion of stress corrosion by the corrosive environment. The cold spray coating produces compressive stress on the joint,which can significantly reduce the residual tensile stress of the joint, reduce the interaction of internal and external tensile stress and delay the rate of stress corrosion cracking.