Bacterial leaf streak (BLS) is one of the most important diseases of rice, and as the climate warming; it has a worsening tendency to occur year by year that greatly affect the production. In 2013, BLS broke out in some rice planting areas of Jinhua City, Zhejiang Province, and caused decline over 30% of rice yield in some field with serious disease. Adopting the method of plant tissue pathogen isolation from pathogenic leaves, 6 bacterial strains were isolated and purified, the typical strain JH01 was selected to inoculate the rice seedlings to validate Koch's law. The disease symptoms of inoculation were consistent with the disease occurred in nature, and the same strain was re-isolated from the infected rice leaves. And proved that strain JH01 was the pathogen of rice BLS. The strain JH01 was characterized as Xanthomonas oryzae pv. oryzicola by morphological observation, routine physiological and biochemical indices tests, and 16S rDNA sequences and homology analyses.