The AhDREB1 gene, cloned from Atriplex hortensis L., was transferred into black locust (Robinia pseudoacacia L.) by an Agrobacterium-mediated transformation. The results suggest that stems of black locust sub-cultured in vitro for 20 d are suitable for genetic transformation. The optimum concentrations of kanamycin and cefotaxime were 30 and 150 mg.L-1, respectively. Impor-tant factors affecting the transformation efficiency were studied by means of a L9(34) orthogonal design. An effective system for ge-netic transformation in black locust was developed as follows: the stems were pre-cultured for 2 d, immersed in the Agrobacterium solution (OD6oo = 0.7) with 10 mgL-1 acetosyringone for 21 min and then co-cultured for 2 d. The selection pressures, changing from low to high, could improve transformation efficiency. The transgenic plants were identified by a PCR method. The PCR results indicated that the AhDREB1 gene had been integrated into the genome of black locust and two lines of the transgenic plants were obtained.