Abstract: In this paper, authors have investigated the changes of physiologcal indexes of Fraxinus velutina under various NaCl concentrations. The results are as follows:(1)The absolute germination percentage, germination viability, germination index and vitality index decrease with salt concentrations increased.(2) Free proline contents of the leaves of seedling leaves under different salt concentrations increase compared with the control, and the variations among them are noticeable.(3) With NaCl concentrations increased, the contents of Na + and the ratio Na +/K + of leaves increase, But the survival rates of seedlings decrease.