Abstract: The effects of the use of natamycin and complex with Vitamin C(V_C)on the control of Botrytis cinerea of postharvest blueberry fruits were studied. The minimal inhibitory concentrationsof V_C solution,natamycin solution,natamycin and complex with 20 mg/L Vitamin C(V_C)solution were determined by in vitro experiment. Morbidity,lesion diameter,protein content,and the change of enzyme activity related to disease resistance was studied to determine the inhibitory effect of different solutions on Botrytis cinerea of postharvest blueberry fruits.The results showed that the minimum inhibitory concentrations of natamycinand natamycincombination with 20 mg/LV_C compound solutionfor 5×10⁶ CFU/mL were 1 and 0.5 mg/L,while the antibacterial effect of 20 mg/L V_C was not obvious,indicating that the usage amount of natamycin could be reduced and the anti-bacterial ability could be enhanced by mixed with 20 mg/L V_C. The best natamycin concentrationof the mixture was 30 mg/L.