In order to research the effects of modified atmosphere on the preservation of Pteridium aquilinum during storage period, the SOD and POD activity, respir ation rat e and ethylene release，fresh and dry weight, MDA, chlorophyll, soluble sugar an d VC content were studied by setting different CO2 and O2 proportion. Result s showed that, proper CO2 and O2 proportion can maintain the higher SOD and POD activity, decrease the content of MDA, keep the respiration rate and ethylen e release appropriately, reduce the loss of dry and fresh weight, eventually ava il to the preservation of chlorophyll, soluble sugar and VC content. In this exp eriment, the optimal CO2 and O2 proportion is 2% and 6%, second is 6% and 10 %. The combination could commendably retain the quality of Pteridium aquilin um up to above 15d.