A hydroponics was used to study the physiological response of Saussurea ussuriensis. to Pb stress. Two samples of S. ussuriensis were from a Pbpolluted area in Huixian and a nonpolluted area in Gannan, respectively. The aim was to explore the ecological adaptation mechanism of the two S. ussuriensis populations to Pb stress. The results showed that, at different Pb concentrations, the chlorophyll content of S. ussuriensis from the polluted area increased first and then decreased, while that from the nonpolluted area showed a decreasing trend. The antioxidase enzyme activity of both S. ussuriensis populations increased first and then decreased, but the resistance of S. ussuriensis from the polluted area was stronger. The MDA contents of both S. ussuriensis populations increased with Pb concentrations, but it was significantly higher in the nonpolluted group than in the polluted group. The soluble protein contents of both S. ussuriensis populations decreased, being significantly higher in the polluted group than in the nonpolluted group. The variations in physiological indexes of S. ussuriensis from the polluted area indicated an adaptive evolution, forming a heavy metalresistance ecotype.