Abstract: The effects of potassium nutrition on the growth,soluble carbohydrate content,electrolyte leakage and MDA content,and the activities of antioxidant enzymes of different genotypes wheat seedling were investigated under NaCl(100 mmol/L) stress using sand cultivation under laboratory conditions.The results indicated that application 510 mmol/L K+,could increase the growth of shoots and roots and water content,and consequently alleviated the intimidation of salt.The soluble carbohydrate content in salt tolerant variety(DK961) was increased with the increasing of the K+ concentration at the earlier stages,but decreasing at the later stages.However,it was decreased in the whole stages for the salt sensitive variety(JN17).The electrolyte leakage and MDA content was similar with CK of two varieties under 10 mmol/L K+ treatment.The antioxidant enzymes activities in both varieties were firstly increased to a peak value and then declined afterwards.The activity of POD was more significantly affected by K+ concentration than that of CAT.In conclusion,proper ratio of Na+/K+ in the exoteric solution could alleviate the negative impact of salt stress on wheat seedling.Base on the result,the ratio of Na+/K+ 10∶1 was recommended.