The effect of neodymium on the silver nanoparticles prepared by vacuum deposition has been studied by TEM, EDX, HEED and XRD. Experimental results show that the size of silver particle decreases, its XRD peak disappears, and the component related to neodymium is amorphous due to the adding of neodymium. It is considered that the neodymium adding can increase the activation energy for surface diffusion to be 0. 071 eV, and the adsorption energy to be 0. 142 eV - 0. 426 eV based on the theory of Lewis-Campbell.