Abstract: Distributions of residual stresses in diffusion bond of dissimilar materials were simulated by FEM calculation.Results showed that destructive residual stresses presented in the minute area adjacent to bond line of the base material with smaller coefficient of expansion.Reducing bond temperature and diminishing bond time are in favor of the mollification of interface stresses.Concepts of the residual stress factor R_f and the thickness factor T_f were propounded.As selecting active layer,the interlayer with smaller|R_f|and T_f should be given precedence,and with a prerequisite of sufficient physical contact a small thickness of the interlayer is finer.