Abstract: The sdudies of the characteristic of photosynthesis, transpiration rate, water use efficiency, electrolyte exosmosis rate, Na⁺ and K⁺ content, soluble salt content, free proline and soluble sugar content of seedlings of Puccinellia tenuiflora were concerned under salt stress.The result indicated that salt tolerance of the seedlings of P.tenuiflora based on its characteristic of photosynthesis and transpiration salt tolerance, and better ability of osmotic regulation.