With three different salt tolerance Brassica napus inbred lines 2205(strong salt-tolerant),487(medium salt-tolerant) and 1423(sensitive) seedlings as tested materials,we studied the variation of several physiological indexes(the contents of MDA,soluble sugar,betaine and chlorophyll) after NaCl treatments 0(CK),60 mmol·L^-1(low salt),120 mmol·L^-1(mid-low salt),180 mmol·L^-1(medium salt),240 mmol·L^-1(high salt) and its relationship with salt resistance in the 5-leaf stage by soil culture and hydroponics,to provide theoretical guidance for the evaluation of rapeseed salt tolerance.The results showed that:(1)Leaf MDA content under low salt and mid-low salt stress reduced and significantly lower than that of CK(no salt stress),under medium salt and high salt stress significantly increased,and the content in 2205 is the lowest and increase the minimum,while the content in 1423 is the highest and furthest.(2)Leaf soluble sugar content reduced under low salt and mid-low salt stress,(but for 2205 that is significantly higher than that of CK under mid-low salt stress),increased under medium salt and high salt stress and is significantly higher than that of CK.The soluble sugar content is the highest level and the biggest increase in 2205,and significantly higher than that in 487 and 1423.while the soluble sugar content is the lowest and the smallest increase in 1423.(3)The betaine content increased with the increase of concentration of NaCl.The content were significantly increased in 2205 and 487 above the mid-low concentration of salt stress,only raised significantly in 1423 under high salt stress.The content is the most and the highest levels in 2205 and the lowest and the smallest increase in 1423.(4)Leaf chlorophyll content increased significantly under low salt and mid-low salt stress,of which is the highest levels in 2205 and the biggest increase.The chlorophyll content significantly reduced under medium salt and high salt stress,especially under high salt stress the chlorophyll content is low,of which is the lowest and highest reduce in 1423.This study can be concluded that below the mid-low salt concentration(120 mmol·L^-1),NaCl stress may promote the rape seedling growth;above the medium salt concentration(180 mmol·L^-1),rape seedling growth was significantly inhibited,rapeseed will be more severe injuries with the higher NaCl concentration.At rapeseed seedling growth stage,the physiological indicators changed significantly when NaCl stress concentration at the 120-180 mmol·L^-1;this concentration range may be suitable for the identification of salt resistance strength.Various physiological indicators showed that 2205 with strong salt resistance,1423 with the worst salt resistance,which are consistent with the actual performance of germination stage and seedling stage result.