Abstract: The photosynthetic characteristics,the content of chlorophyll,carotenoids and soluble sugar in tobacco leaves were analyzed after physical drought stressed.The results showed that after physical drought stressed,the initial fluorescence(Fo) and non-photochemical quenching(qN) of transgenic tobacco increased,but were significantly lower than wild-type.Other fluorescence parameter lower rates were significantly lower than that of wild-type.The photosynthetic parameter and chorophyll content of both samples decreased,but the lower rates were significantly lower than that of wild-type.The content of soluble sugar of transgenic tobacco was significantly higher than wild-type.These results indicated that the BnDREB1-5 transcription factor gene had an effect on drought stressed.