In response to the high sensitivity of joint cracks and poor mechanical properties of T8 2195 Al-Li alloy during argon arc welding， the development of 2195 Al-Li alloy welding wire was carried out， and the microstructure， crack resistance， and comprehensive mechanical properties of the joint were studied. The results indicate that the 2195 Al-Li alloy fusion welding joint is mainly composed of α-Al， Al₂Cu and Al₃（Ti，Zr） phases， it has excellent crack resistance and mechanical properties.Its crack sensitivity K₁ is less than 1%， K₂ is 0%， and the tensile strength of the joint at room temperature is about 390 MPa，and elongation is 6.3%. The development of BJ-4505 welding wire provides technical support for the engineering application of 2195 Al-Li alloy.