Abstract: Fresh Hami jujube was used to study the effect of different concentrations of CO2 and O2 treatments on its anaerobic respiration metabolites, activity of the enzyme and accumulation of anaerobic respiration metabolites after a constant temperature of 50℃ drying. The results indicated that the content of pyruvate reached a peak and then declined with different concentrations of CO2 treatment, and showed a downward trend processed by the low O2. The activity of PDC and ADH increased at first and then decreased. The 5% CO2-treated, 10% CO2-treated samples reached maximum activity in 2nd day, 4th day respectively. The low O2-treated samples had small change of PDC and ADH activity variation than high CO2-treated samples, indicating that metabolism of anaerobic respiration was more sensitive to CO2 than O2 on Hami jujube. The content of ethanol had a degree of accumulation after being treated. The 10% CO2-treated samples reached a peak at 4th day, the value was 0. 1855%. The content of acetaldehyde and ethanol were high in dried jujube after a constant temperature of 50℃ which were treated by CO2 and O2.