Abstract: 【Objective】 In this reaearch, the content change law of phenolic acids and the synthesis pathway for benzoic acid in Jun jujube in different periods were preliminarily determined. 【Methods】 In this study, HPLC-MS/MS method was used to determine the content of phenolic acids related to benzoic acid synthesis in Jun jujube from three producing areas in Xinjiang, and Duncan's difference significance analysis method. 【Result】 The results showed that benzoic acid content accumulated with the growth timeThe content of trans cinnamic acid and benzoic acid in Junzao was the highest in Kashi area, reaching 69.25 mg/kgThe content of phenolic acidsin Jun jujube were as follows:benzoic acid>salicylic acid> p-coumaric acid>trans-cinnamic acid. 【Conclusion】 The results showed that benzoic acid produced by endogenous metabolism of Jun jujubehe content of four phenolic acids in Jun jujube from different producing areas was significantly different(P<0.05).