Abstract: Salt stress is one of the most important factors limiting plant cultivation. Seed germination and seedling are markedly harmed when it is cultivated in Soil salinity.the effects of different concentrations of NaCl on the germination of Swainsona salsulaTaub seeds were studied. It was showed that the germination was delayed in higher concentration of NaCl, and the relative germination index, the relative vitality index of Swainsona salsulaTaub seeds were all decreased. And there was no germination in 500 mmol/L NaCl solution,the conductibity and content of praline in the leaf was increased in higher concentration of NaCl, it is implied that the inhibition of membrane restoration might be one of the important reasons for the postponed germination and declined germination vigor under salt stress. In addition, the content of proline might be related to the salt tolerance.