Ag dendrites have inspired considerable research because of their fascinating hierarchical structures, unique optical properties, and widespread applications. However, the intrinsic structures and exact growth process of the Ag dendrites are still far from being completely understood and need to be investigated further. In this paper, well-defined silver dendrites with primary-, secondary-, and higher-order branches have been prepared by conventional redox displacement. The structures of as-prepared Ag dendrites have been systematically investigated by SEM, SAED and HRTEM. The results of SAED and HRTEM reveal that the well-defined silver dendrites have single crystal nature with many defects existed in every level structure. A mechanism based on site-specific sequential nucleation and the subsequently preferential growth along principal crystallographic axes under a non-equilibrium condition was proposed to explain the formation of Ag dendrites in the present case. (c) 2012 Elsevier B.V. All rights reserved.