Abstract: 【Objective】 In 2018, a new disease causing the fruit bacterial streak on pepper was discovered in the pepper planting area of Hexud County in Xinjiang. This project aims to clarify its pathogenic species, and provide basis for further research on the disease regularity in field and control the disease. 【Methods】 Tissue separation method, Koch's postulates, morphological observation, physiological and biochemical characteristics determination, 16SrDNA gene phylogenetic analysis were used to identify the pathogen of the disease. 【Results】 Thirty single colonies were isolated and purified from the surface of diseased fruits collected in the pepper field. Through the pathogenicity back inoculated by acupuncture inoculation method, four pathogenic strains were obtained. They were consistent with the morphological characteristics and physiological and biochemical test results. The phylogenetic tree results showed that the four pathogenic strains were grouped into one branch: Pseudomonasargentinensis that was reported, and the similarity with the model strain P. argentinensis CH01T (accession number: AY691188) reached 99.2 %. 【Conclusion】 The pathogen of pepper bacterial streak in Hexud County in Xinjiang was identified as P. argentinensis.