This thesispresents a series of mechanical test methods and comprehensively investigatesthe deformation and damage behavior of Cu/Pb-free solder joints under differentloading conditions. The fracture behavior of Pb-free joint interfaces inducedby stress, deformation of solder and substrate are shown, the shear fracturestrength of the Cu6Sn5 IMC is measured experimentally for the first time, andthe dynamic damage process and microstructure evolution behavior of Pb-freesolder joints are revealed intuitively. The thesis puts forward the argumentthat the local cumulative damage is the major cause of failure in solderjoints. The research results provide the experimental and theoretical basis forimproving the reliability of solder joints.