Abstarct: Zinc aluminate spinel (Gahnite) has drawn considerable attention as a catalytic material with desirable properties such as high thermal stability, high mechanical resistance, low temperature sinterability, better diffusion and ductility, and low surface acidity. Due to these properties, it was used as a high temperature material, catalyst, catalyst support, and optical coating. In general, there are several preparation methods for ZnAl2O4 spinels, such as solid state-reaction, precipitation or co-precipitation, sol–gel, hydrothermal, molten salt, etc. In recent years, preparation of ceramic powders by sol-gel process and hydrothermal method has attracted a considerable interest. Part of this interest was caused by the fact that these methods offer good grip for control of morphology, homogeneity, surface area and pore size distribution in comparison to conventional routes. The effects of various parameters, including hydrothermal processing temperature, solvent polarity and the type of precursor in development of the zinc aluminate phase by hydrothermal-assisted sol-gel processing has been studied. In the present work, aluminum t-butoxide and aluminum 2-butoxide as aluminum precursor and zinc chloride as zinc precursors mixed in stoichiometric ratio with 0.25M concentration in a mixture of toluene and 2-butanol. The mixture then hydrolyzed in a stainless steel reactor at different temperatures (50-200 ºC). The produced gels dried at 100ºC overnight and calcined at 700 ºC for 3 hours. The product powders have been characterized by FT-IR, PXRD, SEM,BET and TG/DSC. It was concluded that Zn(acac)2 as zinc precursor, polar protic solvents such as alcohols and hydrothermal process at 50ºC were more appropriate for the preparation of pure single phase zinc aluminate with particle size of 9-27 nm.