Abstract: According to the requirements for mechanical property of fan impeller welded joints,cored wire was designed based on the principle of microstructure match.The component gap between the tested cored wire and designed cored wire was filled by alloying elements transition of the coating.An electrode special for 0Cr13Ni5Mo steel was developed after metallurgical analysis, mechanical and processing property testing.The results show that the method of filling the component gap between the tested cored wire and designed cored wire by alloying elements transition of the coating could verify whether the designed cored wire achieved the purpose and also guide the small batch production of special electrodes.The microstructure of the weld and heat-affected zone (HAZ) made with the No.1,No.2 and No.3 electrodes consisted of tempered sorbite,lath martensite,residual austenite and quadratic precipitated phase,and the mechanical properties of the resultant joints were better than those with the No.4 electrode.The No.2 electrode had the best processing property,and the No.3 electrode had the best comprehensive property which could be used as a special electrode for 0Cr13Ni5Mo steel.