Abstract: In this paper, two real crystals of Ag and Ni were selected. The following two conditions were studied by the Molecular Dynamics (MD) simulation method: the first one is that the two bulk metals are too far to form interface; the second one is that they form interface. By simulating the static relaxation and dynamics bending process, the differences between the two conditions were compared. The results show that the existence of interface affects greatly, sometimes even controls the mechanical properties of the composite.