In order to improve the connection performance and welding quality of high-strength aluminum alloy joints,the performance of three different connection joints,namely 2024-T42 aluminum alloy refilled friction stirring spot welding (RFSSW),resistance spot welding and riveting,was characterized and analyzed by microstructure observation tests,tensile tests,tensile shear tests and microhardness tests.The results show that the mechanical properties of the RFSSW joint are the best,and the tensile shear property is 7.23 kN,which is 115.82% higher than riveting property and 37.45% higher than resistance spot welded joint;the pull-off mechanical property is 3.09 kN,which is 3.69% higher than riveting and 137.69% higher than resistance spot welded joint;the microhardness of RFSSW joint is the highest,which is close to the base metal,while the microhardness of resistance spot welded joint is the lowest,which is only 50% of the base metal.The fracture morphology of RFSSW and resistance spot weld joints are ductile fracture and mixed fracture,respectively.Using RFSSW method can improve the joint performance of aluminum alloy spot welding,which provides a theoretical and technical basis for the application of aluminum alloy structural spot welding.