Abstract: The twin spot laser welding could significantly improve weld quality.For aluminum, surface quality was improved with fewer surface defects such as undercut, surface roughness, spatter, and underfill.The microstructure of twin spots laser welding joint of 5052 aluminum alloy with 2.0 mm thickness was observed. The mechanical properties, such as the microhardness and the tensile properties at room temperature were also tested, meanwhile the fractography was observed.It is shown that the structure of twin spot laser welding is finer and the microhardness is higher than the ones of the base metal, but lower than single laser welded joint.Meanwhile the tensile properties of twin spot laser welding is higher than that of single laser welded joint and the base metal.