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 7h. The results indicated that water-holding capacity of 35S: BnDREB1-5 transgenic tobacco leaves was 62% higher than 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 in wild-type leaves as large as in transgenic tobacco.