Abstract: Hengshan Astragalus membranaceu leaves were used as the experimental materials.The experimental method was used to induce hairy roots by Agrobacterium rhizogenes infection.The ability of different strains to induce hairy roots from leaves and the genetic transformation system of hairy roots were studied, including effect of different explants, bacterial concentration, co-cultivation time, antibiotic type and concentration, and acetosyringone concentration on hairy root induction rate and the contents of total flavonoids and total saponins in hairy roots cultured on large scale were determined, a stable hairy root system of Hengshan Astragalus membranaceus were established, in order to provide reference for establishing a liquid culture system of hairy roots that accumulate active ingredients.The results showed that the induction rate of hairy root was higher when the leaves were used as the explant, soaked for 30 minutes by OD₆₀₀=0.6 LBA9402,co-cultured for 3 days, cultured in 1/2 MS medium containing 100 μmol·L^-1 acetosyringone, selected on screening medium with 500 mg·L^-1 cefixime.The induction rate of hairy root was 54.1%.It was confirmed by PCR analysis that the rooting gene in the LBA9402 was integrated into the genome of Astragalus membranaceus.The content of total flavonoids and total saponins of hairy roots increased significantly after liquid culture expansion, which were 1.72 times and 2.31 times that of natural roots, respectively.