Agitator impeller consist of turbine blades, positioning plates, central axis, flange, blocking plate and steel by welding, It is a typical welded structure. In the production process easy to produce deformation, cracks, undercut, not fusion, porosity and other defects, affecting life,and it is important for tacking and welding for turbine blades and positioning plates. In order to prevent the generation of welding defects, to meet the design requirements, The process of tacking and welding for turbine blades and positioning plates is designed in this paper.