Abstract:Citrus yellow shoot disease (citrus huanglongbing) leaves of Citrus maxima cv. Shatianyou collected from pommelo orchard in Meizhou, Guangdong Province, showed typical symptom of leaf mottling. The pathogen which was observed under electron microscopy was similar in morphology and structure to bacteria-like organism of citrus huanglongbing disease. Polymerase chain reaction (PCR) analysis also proved that the DNA of the pathogen was greatly homologous with PCR product from that of citrus huanglongbing pathogen. The result exhibits that the citrus yellow shoot could infect pommelo, which seldom appeared in this fruit.