Abstract: The biological properties on tobacco with 35S:BnDREB1-5 transformation were analyzed which included the holding water capacity,the size and density of upper and lower epidermis stomata,the content of chlorophyll,and plasma membranes permeability after physical drought stressed 7 h.The results indicated that water-holding capacity of 35S:BnDREB1-5 transgenic tobacco leaves was 62% of that of wild-types.The upper epidermis stomata apparatus was bigger in transgenic tobacco than wild-type,but the opening of stoma was smaller in upper epidermis than wild-types.The stomata density was 1.5 times in wild-type leaves as large as in transgenic leaves.The content of chlorophyll was 29% higher in leaves of wild-type than in transgenic leaves,and the plasma membranes permeability were 1.4 times as much as in transgenic tobacco.