In this study, adventitious roots of Panax quinquefolium L. have been successfully established. The highest induction rate of roots was obtained in MS medium containing 3 mg L⁻¹ IBA after 4 weeks of culture. The culture conditions of adventitious root were optimized and evaluated with response surface methodology. The best culture conditions for root growth seemed to be 0.75 salt strength MS medium, 4.70 g L⁻¹ inoculum size and 40 days of culture. The active component contents of adventitious roots were compared with those of native roots. The total saponins content was found to be 16.28 mg g⁻¹ in native root and 4.64 mg g⁻¹ in adventitious root. The polysaccharide content of the adventitious root was 1.5 times higher than that in the native P. quinquefolium (30.54 vs. 20.28 mg g⁻¹).