Abstract: Taking root mustard as the test material, using PE packaging method and storing at low temperature（2±1）℃,the effects of 0.01 mm PE cling film packaging on the quality and ultrastructure of root mustard during storage was studied, in order to provide a reference for the storage of root mustard.The results showed that 0.01 mm PE cling film could inhibit the increase in weight loss rate of root mustard,slow down the respiration rate,delay the decrease in hardness,inhibit the increase in cellulose content,increase the activity of catalase and superoxide dismutase,and delay the increase in intercellular space,improve its flavor substances and effectively extend its storage period.