Abstract: A regulator of secondary wall thickening and cellulose content in plants, COBRA encodes glycosylphosphatidylinositol-anchored protein and is closely associated with the physiological and chemical functions of a tea plant. From the available data on Camellia sinensis genome, this article identified the specific genes and analyzed by bioinformatics the physicochemical properties, subcellular localization, evolutionary relationship, conserved domain, and chromosome localization of the gene family. The effects brought about by COBRAs on the PEG induced stresses, such as drought, methyl jasmonate treatment, and salt, on tea plants were studied. And the gene expression in the methyl jasmonate treated plants was verified by fluorescent quantitative PCR. The 16 members identified in the COBRA family had relative molecular weights ranging from 24,807.70 to 74,813.12 kDa, isoelectric points from pH 5.43 to 9.14, and subcellular localization in the cell membrane and outside nucleus. The phylogenetic tree of the family divided the members into 5 distinct groups. All conservative domains and motifs of a gene in a same subfamily belonged to the COBRA family. The COBRA expressions differed in varied plant parts or under different stresses. Thus, the genes appeared to be involved in the functions of the plant growth and development as well as the abiotic stress response. The real time fluorescent quantitative PCR on the genes of tea plants treated by methyl jasmonate displayed expression variations among the 3 CsCOBRAs to generally concur with the transcriptome data.