In this study, qRTPCR was applied to detect the temporal and spatial expression specificity of BjuA09DFR gene. In addition, the BjuA09DFR gene promoter was cloned, and the promoter GUS fusion expression vector of BjuA09DFR gene was constructed. We transferred the fusion expression vector into Arabidopsis thaliana by Agrobacteriummediated floral dip method. The expression pattern of BjuA09DFR gene promoter was analyzed by GUS histochemical staining in different tissues during the different development periods, which provided theoretical basis for further study of the function of BjuA09DFR gene promoter. The results showed that: (1) BjuA09DFR gene could express in multiple tissues of Brassica juncea, especially highly expressed in leaves, flowers, silicles and seeds of 15 days after pollination. (2) The fusion expression vector of GUS gene drived by BjuA09DFR gene promoter (pBjuA09DFR∷GUS) was successfully constructed，and transformed into wildtype A. thaliana by Agrobacteriummediated method. We successfully obtained positive transgenic plants by screening test of resistance to kanamycin and PCR detection. (3) Histochemical analysis of GUS showed that the GUS activity of transgenic A. thaliana displayed obviously temporal and spatial specificity, with the deeper staining in leaves, flowers, silicles and seeds of 15 days after pollination.