The new nanohybrid of molybdenum peroxo compounds based on pyridine dicarboxylate ligands were synthesized by employing one-pot procedure in aqueous media and characterized by infrared (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermal analysis (TGA/DTA). The prepared compounds were used as catalysts for the epoxidation of cyclohexene and cyclooctene in a mild condition. Results showed that these molybdenum peroxo compounds have significant potentials as oxidants in oxygen atom transfer reactions. These reagents oxidized olefins to epoxides in presence of hydrogen peroxide with high conversions and selectivity. Comparison of the relative reactivity of those compounds shows that the electronic nature of ligands influences the rate and activity of oxygen transfer reaction. It is also found that the addition of organic ligands not only prevented the formation of diols in epoxidation of alkenes, but also increased the reaction rate.