Abstract: Six cut chrysanthemum varieties were treated with different concentrations(0,20,40,60 mmol·L^-1) of Na₂CO₃.The growth and physiological indexes of different chrysanthemum varieties were measured and their alkali resistance was comprehensively evaluated by principal component analysis and subordination function.The effects of alkali stress on the morphological changes and physiological indexes of different cut chrysanthemum varieties were studied, in order to provide reference for the promotion of chrysanthemum varieties in northwest saline alkali areas.The results showed that under alkali stress, there were significant differences among various indexes of different varieties, and the growth was inhibited.The plant height, leaf length, leaf width, leaf number, chlorophyll content（SPAD） and relative water content（RWC） of leaves were decreased significantly with the increase of the stress level.The most obvious drop was ‘Kaiwenfen’ and ‘Yinxingzi’;compared with CK,the relative electrical conductivity（REC） and malondialdehyde（MDA） content of Na₂CO₃ treatment increased significantly, while the superoxide dismutase（SOD） and peroxidase（POD） increased first and then decreased.Using principal component analysis and membership function analysis, four principal components were extracted, and the cumulative contribution rate reached 86.442%.The indicators with high score coefficient include REC,MDA content, SOD activity and leaf width, which could be used as important indicators for screening and evaluation of alkali tolerance.According to the value of D,the six chrysanthemum varieties were ranked in order of alkali resistance, ‘Gongzhuxin’＞‘Funi’＞‘Tiaowen’＞‘Hancheng’＞‘Yinxingzi’＞‘Kaiwenfen’.‘Gongzhuxin’ has relatively strong alkali resistance, which could be popularized as an alkali resistant variety, followed by ‘Funi’,‘Kaiwenfeng’ had the weakest alkali resistance.