The quality of 0.50% water-soluble chitosan(WSC) and carboxymethyl chitosan(CMC) coatings on postharvest green asparagus which were stored at 2℃ was investigated.Base on the data of sensory evaluation,weight loss percentage,the contents of ascorbic acid,chlorophyll,malonaldehyde(MDA),total phenolic and polyphenoloxidase(PPO),peroxidase(POD),super oxygen dehydrogenises(SOD) activity testing,both 0.50% WSC and CMC treatments could dramatically retard the decrease of weight loss,firmness,the loss of chlorophyll and ascorbic acid during the storage.Moreover,0.50% CMC treatment not only could keep the total phenolics content,but restrain the changes of PPO,POD,and SOD activity,presenting better quality of asparagus than the control during the cold storage,and prolong the shelf life of postharvest green asparagus to 35 days.