Abstract: The effects of topdressing different nitrogen levels on the growth of Suaeda salsa and on the improvement of saline soil, were conducted in field experiments where growth, accumulative amounts of K⁺, Na⁺, Ca²⁺, and Mg²⁺ of S. salsa, as well as salinity concentrations in soils were assessed. The yields of grain, stem, leaf and biomass increased with N topdressing. At the rate of 450 kg/ha, the biomass of component factors in S. salsa presented a linear growth trend with the amount of N topdressing. With a further increase of nitrogen application, the concentrations of K⁺, Na⁺, Ca²⁺, and Mg²⁺ barely changed. The accumulative amounts of K⁺, Na⁺, Ca²⁺, and Mg²⁺ increased with N topdressing. The concentrations of K⁺ and Na⁺ in surface soils (0-10 cm) showed decreasing trends with N topdressing. N fertilisation could therefore stimulate S. salsa growth and strengthen the effectiveness of bioremediation of saline soil.