Chiral (salen)Mn(III) complexes were immobilized into mesoporous helical silica for asymmetric epoxidation of unfunctionalized alkenes, and chiral synergistic effects between supporting material and (salen)Mn(III) were investigated. Characterization revealed both carriers and supported catalysts had a hierarchical structure composed of morphology and internal channels. Supporting materials had helical morphology and excessive left-handed channels, while most supported catalysts still had excessive left-handed channels although their morphology might degrade. Catalysis revealed the synergistic effects between mesoscopic and molecular chirality exist, and the combination of left-handed channels with (R,R)-(salen)Mn(III) appeared to be more enantioselective than that with (S,S)-salen counterpart in epoxidation of terminal and cyclic alkenes. [GRAPHICS] .