Abstract: A pot experiment was conducted to determine the effects of mixedalkali (the mole ratio of NaHCO3 and Na2CO3 is 9:1) at different concentrations of 100, 200, 300, and 400 mmol/L mixtures on physiological characteristics in leaves and plant height of TamarixchinensisLour. seedlings. The results showed that in comparison with the control, the relative water contents in leaves of TamarixchinensisLour. were significantly decreased at the alkali concentrations of 100, 200, 300, and 400 mmol/L by 8.82%, 34.49%, 43.27%, and 45.43%, respectively. Whereas the contents of MDA, soluble sugar and proline presented an increasing trend along with the increase of alkali concentrations, and the proline contents in the alkali concentrations of 100, 200, 300, and 400 mmol/L were increased by 36.37%, 56.41%, 77.35%, and 84.25%, respectively, compared with the control. In addition, the size order of plant height in different alkali concentrations was as follows: control>100 mmol/L>200mmol/L>300mmol/L≈400mmol/L, and the plant height in the alkali concentrations of 100, 200, 300, and 400 mmol/L were significantly decreased by 45.95%, 62.16%, 70.27%, and 74.05% in contrast to the control, respectively. This suggested that different degree of alkali stress equally inhibited the growth of TamarixchinensisLour.seedlings. As a result, the alkali stress mainly including NaHCO3 and Na2CO3 had significantly inhibitory effect on the growth of amarixchinensisLour., and as the increase of degree of alkali stress, the inhibitory effect become larger and larger.