Abstract: In order to investigate the impact of the coastal saline soil on the growth and development of Sedum aizoon, and grasp its tolerance to saline soil planting, by five gradient coastal saline soil treatments (3, 5, 7, 9, 11 g/kg etc.), the author studied the growth index and Na , K distribution of Sedum aizoon. The results showed that: with increasing salinity, plant height, branching, fresh weight and dry weight decreased, salinity which was more than 7 g/kg inhibited the growth of Sedum aizoon seriously, but plant could continue to grow with salinity of 11 g/kg; salinity which was more than 9 g/kg significantly inhibited the ground dry matter accumulation, effect of belowground biomass was significantly less than that of aboveground. As salinity increased, the Na content of root, stem and leaf tended to increase, the site content showed as the stem> leaf> root. As the salt content increased, K content of leaf decreased, but that of root and stem tended to increase, K content of the stem and leaf were three times more than that of root. As the salt concentration increased, the Na /K ratio of root, stem and leaf had an increasing trend, and under salt stress of less than 9 g/kg, Na /K ratio of root was nearly four times more than that of stem and leaf. Sedum aizoon had strong salt tolerance, less than 7 g/kg of salt had little influence on it, its salt tolerance characteristics might be associated with its perennial root and structure of stem and leaf.