This work attempts to investigate some unknown properties of ZnO micro- and nanostructures as one of the most promising materials in this decade. Additionally, the interaction between the components consisting of ZnO, buffer layers and substrates can produce new physical properties which may provide some important utilization in electronic and optoelectronic devices. The aim of this work is to study the effect of various substrates with metal or metal oxide layers including Au, Ag, Cu and Au+Cu alloy on the structural, morphological and optical properties of ZnO micro- and nanostructures. In addition, the relevant growth mechanisms are also proposed.