Abstract: Blister blight disease is a disease of Camellia sinensis buds and leaves caused by Exobasidium vexans Massee. Chitinase is an important pathogenesis-related protein in plants. In order to explore the role of chitinase in tea plant resistance to Exobasidium vexans Massee, 28 chitinase genes were screened from the genome of tea plant ‘Yunkang 10 ’ in this study, and homologous cloning of chitinase gene sequences from Camellia sinensis was carried out using highly resistant Camellia sinensis ‘Meizhan’ and highly sensitive Camellia sinensis ‘Qianmei 601’ as materials, and the obtained genes from cloning were analyzed by bioinforma-tics. At the same time, two Camellia sinensises with different resistance were inoculated with Exobasidium vexans Massee, and the expression level of cloned genes were analyzed by real time quantitative PCR at different periods after inoculation. In this study, four chitinase genes were simultaneously cloned from two Camellia sinensises, named CsC8, CsC13, CsC21 and CsC23 respectively. The results of evolutionary tree and conservative domain analysis showed that CsC8 and CsC23 belong to peptidase family, CsC13 belonged to plant chitinase, CsC21 was a chitinase but may not belong to the plant chitinase. The expression levels of CsC8, CsC13 and CsC23 gene in highly resistant Camellia sinensis ‘Meizhan’ were all increased after inoculated with Exobasidium vexans Massee. The expression of CsC8 and CsC13 gene in highly sensitive Camellia sinensis ‘Qianmei 601’ was increased after inoculating with Exobasidium vexans Massee, but CsC23 gene had almost no change after inoculation, and the expression of and CsC13 gene in highly resistant Camellia sinensis ‘Meizhan’ was higher than that in highly sensitive Camellia sinensis ‘Qianmei 601’.Therefore, it was speculated that chitinase CsC13 played an important role in the process of Camellia sinensis resistance to Exobasidium vexans Massee. This study lays a foundation for further research on the mechanism of chitinase gene involved in Camellia sinensis resistance to Exobasidium vexans Massee, and provides a theoretical basis for further research on the function of plant peptidase.