Friction stir welding（FSW） is used to conduct different welding process contrast experiment of 3 mm thick 6005A alloy plate. Through the mechanical tensile,hardness,forward bending,macro metallographic and micro metallogra-phic analysis of the weld position,the optimal welding process is finally determined. Research shows that when the rotational speed of the friction head is 1 200 r·min,-1, and the welding speed is 700 mm ·min,-1,the mechanical tensile fracture occurs near the heat affected zone and the fracture surface shows "necking" phenomenon,the Vickers hardness distribu-tion is W-shaped,and there are small S-lines in the micro-structure. The mechanical value is higher than the standard and better than the other three welding parameters,which meets the production process requirements and provides technical support for the production process.