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To improve the content of ascorbic acid of fresh apple juice, apples of ‘Ralls’ and ‘Fuji’ juice were prepared after cold stress, and then some important quality indexes were measured. Contents of total ascorbic acid, AA and DHA of ‘Ralls’ and ‘Fuji’ reached maximum values after 20h and 8h of cold treatment at (-7±0.5)℃, respectively. Compared with the apples without cold treatment, contents of total ascorbic acid, AA and DHA of ‘Ralls’ and ‘Fuji’ were increased about 26.65%,，28.93%,，18.26% and 15.78%，17.33%,，11.30%, respectively, and the contents of soluble solid, soluble sugar and malic acid were declined about 8.21%, 13.04%, 7.27% and 11.46%, 14.14%, 7.14%, respectively. Fresh juice was prepared at room temperature within 30min after cold treatment at (-7±0.5)℃. Compared with the juice of apples without cold treatment, contents of total ascorbic acid, AA and DHA of ‘Ralls’ and ‘Fuji’ were increased about 31.26%, 35.40%, 20.54% and 18.05%, 20.46%, 13.33%, respectively, and contents of soluble sugar, malic acid and sugar-acid ratio were declined about 12.03%, 7.54%, 5.92% and 14.53%, 10.00%, 5.04%, respectively; aroma substance was increased by 6 and 5 kinds, and its contents increased about 2.03% and 8.02%, respectively. The results indicated that cold stress could be considered as an effective measure to improve the contents of ascorbic acid for fresh apple juice.