Double-sided welding of single-axis shoulder friction stir welding technology for 6082-T4 aluminum alloy large thickness plate,after the welding,the heat treatment is completed to the T6 supply state. The results of the slow strain rate tensile of the joint samples in the simulated seawater solution and air were compared,and the SCC index was compared to determine the sensitivity of the specimen to stress corrosion. The results show that 6082-T6 aluminum alloy heavy plate friction stir welded joints（surface and middle layer） have good stress corrosion resistance. However,the stress corrosion sensitivity of the middle welded joint is greater than that of the surface layer. The SEM scan results show that test joints are fiber-like in both inert and corrosive media without obvious inclusion defect and brittle cracking characteristics,and whether the edge or the center is composed of a large number of dimples,it is a typical ductile fracture.