In order to explore the characteristics of acid tolerance of rapeseed at the seedling stage in acidic soil environment，113 rapeseed varieties were treated with acid stress and acid soil improvement by pot experiment. 10 traits including root length，plant height，shoot fresh mass，root fresh mass，total fresh mass，shoot dry mass，root dry mass，total dry mass，root/shoot ratio and SPAD were measured at the seedling stage. The acid resistance of different rapeseed varieties were evaluated by correlation analysis，principal component analysis，membership function method，cluster analysis，grey correlation degree and stepwise regression analysis，the acid-resistant evaluation model was established and the acid-tolerant rapeseed varieties were screened. The results showed that 113 rapeseed varieties showed extremely significant differences in 10 traits under two treatments. The coefficient of variation of 10 indicators ranged from 10.09% to 78.68%. The 10 indicators were converted into 4 independent comprehensive indicators，representing 88.688% of the information content of the original indicators. Based on the cluster analysis of the comprehensive evaluation value of acid tolerance （D value） of 113 varieties，they were divided into 5 groups，namely，extremely acid-resistant type （2 samples），acid-resistant type （16 samples），intermediate type （41 samples），sensitive type （50 samples） and extremely sensitive type （4 samples）. The optimal regression equation was constructed using D value and 10 indicators：D=-0.075+ 0.0403X _{total dry weight}+0.100X _{root fresh weight}+0.188X_SPAD+0.099X_{plant height}+0.092X_{root dry weight} （R²=0.982，F=1 154.562^***），and the suitable identification index of acid tolerance in rapeseed at seedling stage was screened out. In conclusion，acid stress could seriously inhibit the growth of rapeseed at the seedling stage，and there were great differences in acid tolerance among different rapeseed varieties. The acid tolerance of rapeseed could be evaluated by measuring total dry mass，root fresh mass，SPAD，plant height，root dry mass and combining with regression equation.