The invention provides a method for improving a fresh-keeping effect of blueberries. The method mainly relates to the following steps: spraying treatment is performed on blueberry leaves and fruits after fruit setting by using 0.5-1.5 mmol/L salicylic acid (SA) under the condition of rain sheltering cultivation until the surfaces of the leaves and the fruits are completely wet, spraying is performed once every two weeks, spraying is performed for 4 times, after the fruits are mature, sorting is performed, packaging is performed, and the packaged blueberries are stored at temperature of 0 DEG Cor lower. The method provided by the invention effectively improves hardness and antioxidant capacity of the fruits, maintains good quality of the fruits, slows down metabolism of the fruits, and delays an aging process of the blueberry fruits during storage, thereby achieving the purpose of prolonging fresh keeping time; as a natural reagent, the SA plays an important role in the processes of plant development and fruit ripening, and the SA has the advantages of low processing costs, a low using amount and safe and convenient use in an application of fresh keeping of the blueberry fruits; and the method has reasonable design, simple operation and lower requirements on equipment, only needs less costs, and can be widely operated, demonstrated, promoted and applied.