Abstract: In order to explore the effect of exogenous salicylic acid treatment on phenylproanoid metabolic system of postharvest blueberry fruits and its mechanism, fresh blueberry fruits were dipped in salicylic acid solution of 0.5mmol/L and 1.0mmol/L, respectively. Then fruits were moved into a polyethylene film bag with a slackened tie storage at 1℃. During the period of storage, fruit sensory quality, respiration rate, rot rate, firmness and lignin content were measured. Meanwhile, activities of phenylalnine ammonialyase (PAL) , polyphenol oxidase (PPO) and peroxidase (POD) that related to phenylproanoid metabolic were analyzed. The result indicated that exogenous salicylic acid treatments accelerated the process of phenylproanoid metabolism of postharvest blueberry fruits. Therefore, the end product of phenylpropanoid metabolism, lignin content increased and it increased the fruit firmness.