Abstract: Octahedral manganese oxide-based  molecular sieves（OMS-2） were rapidly synthesized by sol-gel method under ultrasonic irradiation with KMnO₄ and fumaric acid as raw materials.The catalytic activities of different manganese oxides applied in the reaction of using 70% aqueous tert-butyl hydroperoxide（TBHP） to oxidize benzyl alcohol for synthesizing benzaldehyde under the solvent free and halogen free conditions were investigated.Results showed that this system was an efficient and environment-friendly catalytic system；the catalytic activity of OMS-2 was very high；and conversion of benzyl alcohol，yield，and selectivity of benzaldehyde were 44.72%，34.31%，and 76.74% at 80 ℃ for 4 h，respectively.Furthermore， after reusing 3 times，the yield，and selectivity of benzaldehyde decreased slightly and OMS-2 was found to have good catalytic activity in the recycle tests.

Key words: octahedral manganese oxide-based molecular sieves, benzyl alcohol, selective oxidation, benzaldehyde