Abstract:SsDREB, which was highly homologous with DREB2 transcription factors from other plants, was cloned from Suaeda salsa L. and its expression was induced by high-salt and drought, not by cold and ABA．In this study, a plant expression vector containing a SsDREB-GFP fusion gene has been constructed and transformed into onion epidermal cells by gene gun method. The result of transient expression showed that the protein encoded by SsDREB was localized in the nucleus. In yeast cells, SsDREB protein was proved to be able to specificly bind to the DRE element and activate the expression of downstream reporter genes. By using agrobacterium-mediated transformation, the SsDREB gene driven by constitutive promoter CaMV 35S was successfully introduced into tobacco (Nicotiana tabacum L.), and the obtained transgenic tabacco plants showed strong drought and salt tolerance. In order to study the molecular mechanism that overexpression of SsDREB increased tolerance to drought and salt stresses in transgenic tobacco, 8 genes from tobacco related with osmotic balance, eliminating active oxygen and improving membrane stability were selected, and their expression in transgenic and control tobacco plants were analyzed by using semi-quantitative RT -PCR method with α -tublin gene as a reference gene under normal growth conditions. The experimental results showed that the 8 genes are regulated by exogenous SsDREB gene, and the expression of 6 genes was significantly higher in transgenic plants than that in non-transgenic plants.