Abstract:Two cantaloupe varieties（'Xiaomi 25'and'Meilong'）in Shandong province were used as experimental materials to study the changes in the storage quality of different varieties of cantaloupes under a controlled atmosphere（CA）with different CO2 concentrations. The results showed that with the prolongation of storage time，treatments under different CO2 concentrations effectively slowed down the weight loss of different varieties of cantaloupe，maintained fruit firmness，and slowed down the decrease of total soluble solids and titratable acid. Moreover，it could increase the activities of peroxidase（POD）and catalase（CAT），slow down the increase of malondialdehyde（MDA）content，and retain antioxidant capacity，finally maintaining good quality at the end of storage. These results suggested that maintaining CA conditions after harvest can help to improve the quality of cantaloupes，prolong the storage period.