Abstract: In order to explore the salt tolerant characteristics of Helianthus tuberosus L., study on saline alkali tolerance of Helianthus tuberosus L. seedlings was carried out. Helianthus tuberosus L. was used as material on the study of different concentration of Helianthus tuberosus L. seedlings under NaCl and Na₂CO₃ stress, to measure the total fresh weight, root, stem, leaf fresh weight, dry weight, chlorophyll content and biomass variation by soilless culture method. The results showed that: 25 mmol/L of low concentrations of NaCl promoted seedling growth, biomass content increased; 100- 200 mmol/L of NaCl inhibited the growth of seedlings, the biomass and the chlorophyll content decreased, with insignificant difference among treatments; when the concentration of NaCl＞200 mmol/L, the biomass surged. The conclusion drawn from the study indicated that low concentrations of Na₂CO₃ promoted the growth of the seedlings, the concentration of Na₂CO₃＞20 mmol/L inhibited the growth of seedlings, the biomass decreased with increasing concentration of Na₂CO₃, chlorophyll content decreased. Helianthus tuberosus L. seedlings were highly influenced under stress of alkaline than salt, therefore, Helianthus tuberosus L. seedlings was salt tolerance.