In this study,Wepresent ZnO thin films using electrochemical deposition method. ZnO thin films are deposited onto metal(Cu) and semiconductor (n-type Si) substrates. The electrolyte consists of a 0.1M Zn(NO3)2 solution, and we applied various potentials at different bath temperatures. XRD shows preferential orientation to (002) that increases with the applied cathodic potential and the bath temperature. Similar tendency is shown on both Cu and n-type Si substrates. SEM micrographs show ZnO surface morphology is greatly affected by the applied cathodic potentials. The RBS analysis reflects the rough morphology of ZnO thin film. The composition ratio Zn:O on n-type Si substrate is determined to be 1.0:1.3 ± 0.3 at the cathodic potential of -1.0[V] and the cell temperature of 70.