Abstract: In order to study on effect of salicylic acid on cucumber seed under NaCl stress, two cucumber varieties (Cucumis sativus L.) (‘Jinchun 5’, ‘Shijichunxiu’) as materials were used to study effects of different concentrations exogenous salicylic acid on germinating characteristics and seedling root growth under 150 mmol/L NaCl stress. The results showed that in 150 mmol/L under NaCl stress, cucumber seed germination and seedling root growth were inhibited under 150 mmol/L NaCl stress, inhibition of cucumber seedling root elongation was more obvious than the germ; exogenous SA could significantly improve the germination of cucumber seeds under NaCl stress, promote seedling root growth, alleviate on growth of cucumber germination and root damage of salt, and SA solution of 0.25 mmol/L treatment was the best for salt stress relieving effect. Under NaCl stress of salt tolerance in different varieties and exogenous SA alleviate the effect existent difference, ‘Jinchun 5’ salt tolerance and exogenous SA alleviate the effect than ‘Shijichunxiu’.