Abstract: Al-Pb alloy thin films were prepared by magnetron co-sputtering.SEM,EDS and TEM were employed to determine the composition and the structure of the alloy films.Meanwhile, the distribution state of Al,Pb atoms in the films was simulated by molecular dynamics.The experimental results showed that the structure of Al-Pb alloy films was affected by the Pb content.When the Pb content in target was less than 4%,Al and Pb atoms could be mixed homogeneously in the alloy film,and the homogeneous alloy thin films could be gotten.With the increating of the content of Pb,Pb atoms tended to agglomerating into inhomogeneous structure,which was consistent with the theoretical simulation.