Abstarct: Supported mextal complexes as heterogeneous catalyst have been used extensively for a wide variety of applications. In these systems, the most important phenomenon is the catalyst elucidation from the support which will be overcome by use of covalent bonding of mextal complexes to the functionalized support. In this research, nano-boehmite with high surface area (326m2/g) and high degree of surface hydroxyl groups, was prepared via hydrothermal assisted sol-gel processing of aluminum 2-butoxide. Then it was covalently functionalized with 3-(tri-methoxysilyl)propyl chloride (CFNB). The terminal chloride group of CFNB then was replaced by ethylene diamine (EFNB). Then vanadium-oxo-acetylacetonate supported on EFNB. ICP analysis showed that vanadium loaded on EFNB was 0.66 mmol/g. XRD experiment confirmed the retention of the nano-boehmite structure after functionalizing and mextal supporting procedures. These supported catalysts were used in epoxidation of cis-cyclooctene and yields of products were investigated by GC. The catalytic procedure for catalyst were optimized for different parameters such as amount of catalyst, solvent, oxidant, temperature and time. It was found that the optimized conditions with over 95% yield for epoxidation of cis-cyclooctene with these heterogeneous nano-catalysts were 20mg of catalyst, 1ml CCl4 as solvent, and 1.12 mmol t-butyl-hydro-peroxide as oxidant at 80ºC. The differences between these nano-catalysts were arisen on total time of catalytic process. The maximum yields were obtained after 60min, for V-EFNB. In addition, recycling experiments revealed that these nano-catalysts could be repeatedly applied for nearly complete epoxidation of alkenes for at least five successive cycles. On the other hand, among these catalysts, V-EFNB can be chosen as the best because it was yielded the maximum efficiency in shorter period of time which is a crucial factor in scaling up the process to pilot plant.