In order to screen the physiological indexes closely related to the saline-alkali resistance of corn，indoor germination and outdoor sand culture tests were used to study the effects of Na2CO3stress on germinationrate，saltdamageindex，embryogrowth，seedlingheight，biomass，proline，malondialdehyde，SOD，soluble protein and otherphysiological indexes of 6 varieties of maize.The method of combination of principal component analysis and membership function was used to evaluate the saline-alkaliresistance.The results showed that the germinationrate，embryogrowth， plant growth and biomass of corn seeds decreased significantly with the increase of Na2CO3stressintensity.With the increase of Na2CO3stressintensity，salt injuryindex，MDA and proline increased gradually in youngleaves.Except NongfuNo.9，the SOD content of other varieties increased with stress intensity.Except Jidan535，the soluble protein content of othervarieties decreased with increasing stressintensity.Using principal componentanalysis，9 indexes including embryogrowth，plantheight，biomass，malondialdehyde and soluble protein were concluded，which were closely related to salt and alkaliresistance.The sequence of salt tolerance strength and weakness of the 6 maize varieties was obtained by fuzzy mathematicsmembership function analysis asfollows:Jidan535>Yulong No.8>Dongdan 969>Nanbei No.1 >Nongfu No.9>Yulong No.2.