Abstract:GRFINTERACTING FACTOR (GIF) gene played important roles in regulating the development of leaf. GIF gene could regulate cell proliferation and expansion to form different leaf sizes. In this study, the gene of CsGIF1 was cloned using RTPCR from leaf cDNA template of tea plant cultivar ‘Longjing43’. In order to clarify the response characteristics of CsGIF1 to abiotic stress, we performed qRTPCR to analyze the expression levels of CsGIF1 under the stresses of high temperature (38 ℃), low temperature (4 ℃), drought (200 g·L-1 PEG) and salt (200 mmol·L-1). This study could lay the foundation for the stress regulation and function study of CsGIF1 in tea plant. The results indicated that: (1) the length of CsGIF1 was 666 bp, encoding 221 amino acids with a highly conserved region called SNH domain. Protein analysis suggested that the CsGIF1 was hydrophilic protein, and its theoretical relative molecular weight is 23 380, theoretical isoelectric point is 6.30, the percentages of acidic, basic, aromatic and aliphatic amino acids are 7%, 9%, 5% and 13%, respectively. Secondary structure prediction showed that CsGIF1 protein consists of 38.01% alphahelix, 10.41% beta turn, 12.22% extended strand and 39.37% random coil, respectively. (2) qRTPCR analysis demonstrated that CsGIF1 gene could respond to the all four abiotic stresses. However, the CsGIF1 gene presented different expression trends to those abiotic stresses. At 2h after the treatment of high or low temperature, the relative expression levels of CsGIF1 gene were upregulated significantly, which was 3.54 and 5.69 times of the control, respectively. Under high or low temperature stress, the response of CsGIF1 gene was significantly greater than under drought or salt stress. Under the treatments of high temperature, low temperature, drought and salt, the expression levels of CsGIF1 showed significant difference in the leaves of C. sinensis cv. ‘Longjing43’.