Plant specific transcription factor (BRI1EMSSUPPRESSOR1，BES1) family involved in regulating the brassinosteroids (BR) signaling pathway and play an important role in plant growth and response to abiotic stress. In this study, the BES1 transcription factor family of tea plant was identified by bioinformatics method. The expression patterns of tea CsBES1 gene in 8 tea tissues were analyzed, and the CsBES1 transcription factor family was expressed at low temperature. In order to reveal the function of CsBES1 transcription factor family and its response to environmental stress, we analyzed the expression of CsBES1 transcription factor family in tea plants under drought and ABA hormone treatment. The results showed that: (1) ten members of the BES1 transcription factor family of tea tree were identified from the whole genome of tea tree, all of which had complete BES1_N domain. According to phylogenetic relationships, 10 CsBES1 transcription factor families were divided into 3 groups, including 2, 3 and 5 members respectively. Each gene of this family contains 2~11 exons. (2) The analysis of tissue expression pattern showed that the expression of BES1 transcription factor family was higher in the young shoots and mature leaves of tea plants, and there were differences among different members. (3) The upstream promoter region analysis showed that there was a lot of ciselements associated with various stress and hormone responses. (4) The results of fluorescence quantitative analysis showed that the expression patterns of BES1 gene were different under different stress conditions. Under low temperature and abscisic acid treatment, the expression levels of CsBES11， CsBES17, CsBES18 and CsBES19 genes increased significantly. However, the expression of CsBES12, CsBES14, CsBES15, CsBES16, CsBES17, CsBES18 and CsBES19 genes increased significantly under drought stress.