In bimetallic cluster, research on the frozen structure with the changing concentration plays an important role in exploring new structural materials. This paper studies the freezing processes of (AgCu)309clusters with different Ag concentrations. The results indicated that the structural transformation was strongly related to concentration. It was found that the frozen structures were changed form icosahedron, hcp and fcc-hcp with the change of Ag concentration. The frozen structures were formed icosahedral for the clusters with Ag concentration at 10%, 20%, 30%, and the pure Ag309. For the clusters with Ag content at 40%, 50%, 60%, 70%, and 80%, the frozen structures were formed defect icosahedral. It was also found that the frozen structure have hcp character for the pure Cu309cluster. Meanwhile, the frozen structure of (AgCu)309with 90% Ag concentration was formed fcc-hcp structure. The segregation effects of the Ag-Cu are the key reason for the structural transformation.