Abstract: Friction-stir welds of 2219 aluminum alloy sheet in 6 mm thickness were completed.The effect of friction stir welding procedures and parameters on weldline formation and mechanical properties of 2219 aluminum alloy was studied.The results show that sound joints could be achieved when rotation speed ranged between 1 250~1 400 r·min-1 and welding speed ranged from 100 mm·min-1 to 140 mm·min-1.The post-weld solution heat treatment and aging of the the 2219 aluminum alloy FSW samples could avcid the softened region could effectively and inerease weld strength.