Abstract: A hydroponic experiment was conducted to study the effects of NaCl concentration on reactive oxygen species，cell membrane permeability，root activity，and the concentrations of Na+，K+，Ca2+，and Mg2+ in different organs of sour jujube seedlings. The results showed no leaf wilting after six days in either 50 or 100 mmol ? L-1 NaCl treatments. In contrast，leaf wilting was observed in both the 150 and 200 mmol ? L-1 NaCl treatments. Leaf H2O2 concentrations were significantly greater in both the 150 and 200 mmol ? L-1 NaCl treatments than in the 0 mmol ? L-1 NaCl（control）treatment. Leaf concentrations were significantly greater in the NaCl treatments（i.e.，50，100，150，200 mmol ? L-1 NaCl）than in the control treatment. The NaCl treatments significantly increased Na+ concentrations in roots，stems，and leaves. In contrast，the NaCl treatments significantly reduced K+，Ca2+，Mg2+ concentrations in leaves. The NaCl treatments had no significant effect on K+ and Mg2+ concentrations，regardless of the plant organ. Compared with the control，the 200 mmol ? L-1 NaCl treatment significantly reduced Ca2+ concentrations in roots and stems. The NaCl treatments significantly reduced the K+/Na+，Ca2+/Na+，andMg2+/Na+ ratios of roots，stems and leaves；However，the K+/Na+ ratio of roots was always greater than 1. In conclusion，in order to adapt to salt stress，sour jujube seedlings not only maintained relative stable K+ and Mg2+ concentrations in roots and stems，but also maintained a K+/Na+ ratio > 1 in roots.

Key words: sour jujubes, NaCl stress, mineral ions, absorption and transportation