The spectra of root,stem,leaf of soybean samples with 0,20,40,60 mg·L^-1 Al3+ were determined by Fourier transform infrared (FTIR) spectrometry with OMNI-sampler.Little difference was found in the spectra of leaf between two soybean cultivars,aluminum-resistant cultivar Zhechun NO.2 and aluminum-sensitive cultivar Zhechun NO.3,except the indices of wave number-absorbance from 928 to 1 200 cm^-1,and similar results were also observed in stem and root samples of the two soybean cultivars with 0 mg·L^-1 Al3+.However,results from the comparison of the spectra showed some distinguishable differences in the intensity and the shape of absorption peaks of their FTIR spectra from 721 to 3 366 cm^-1 of Al-stressed samples and control samples between the two soybean cultivars,and more evident differences of FTIR were exhibited in Al-stressed roots,stems and leaves with higher concentration of Al3+.The increased absorbance at 2 929 and 3 350 cm-1 was found in root FTIR spectra with 20,40,60 mg·L^-1 Al3+, while roots got maximum absorbance at wave number of 1 375 cm^-1 with 20 mg·L^-1 Al3+,which decreased with higher concentration of Al3+,and the same results were showed at wave numbers of 1 410,1 423,1 549 and 1 645 cm^-1.Absorption peak showed maximum at wave numbers of 1 051,2 850,2 929 and 3 350 cm^-1 in stem FTIR spectra with 60 mg·L^-1 Al3+.There was little difference between the spectra of Al-stressed leaves and controls at wave numbers from 1 750 to 2 750 cm^-1,but visible difference in leaf spectra was exhibited at other wave number.Moreover,the results showed that the FTIR spectra of aluminum-sensitive cultivar Zhechun NO.3 showed much more observable differences than aluminum-resistant cultivar Zhechun NO.2 with different concentration of Al,implying that the material metaboly of aluminum-sensitive soybean was evidently affected by Al.Therefore,FTIR spectra could be used broadly for identification of the endurance of different soybean cultivars to Al.