Abstract: For the welding of 40 mm thick 5083 aluminum alloy, 3003/5083 aluminum alloy plates in class Ⅱand Ⅲaluminum containers, the welding tests were carried out by using GTAW and GMAW respectively, and the tensile test, bending test and impact test were carried out.The results show that the welded joints of aluminum alloy thick plates are easy to crack when bending. The measures of circulating water cooling, interpass temperature control, increasing groove angle to reduce the fusion ratio and adjust the Mg content in the weld metal, were proposed to guarantee the plasticity of thick plate welding. After adopting the above measures, the bending performance of aluminum alloy welded joints is qualified, and the tensile strength and room temperature impact toughness are good.