It is significant to take best agricultural measures and improve salinization to rapidly and accurately determinate the composition and content of soil salt. The hyperspectral integrated inversion model based on transformation of hyperspectral, characteristic bands, characteristic spectral indices screening and support vector machine (SVM) was established to improve the accuracy of watersoluble salt ions content by taking the saline soil of Yongji irrigation area of Hetao Irrigation District. The results showed that the correlation between the original spectral reflectance by pretreatment and watersoluble salt ions content was relatively low and the maximum correlation coefficient was 0.18, and the sequence of them from big to small was as follows: Ca2+, SO2-4, Mg2+, the content of salt, Na++K+ and Cl-. The optional transformation forms of salt content, Na++K+, Cl-, SO2-4, Ca2+ and Mg2+ were (1/R)″, (1/R)″, (lnR)′, (lnR)″, R′ and (lnR)″, respectively. The numbers of sensitive bands (P<0.01) were 41, 7, 9, 65, 76 and 28, respectively. Stepwise regression method was used to filtrate the characteristic bands from sensitive bands, and the average of determination coefficient (R2) and the average of root mean square error (RMSE) of each ion in the regression model based on the characteristic band were 0.35 and 0.87g/kg, of which R2 was the largest and the smallest were SO2-4 (0.52) and Ca2+ (0.20), respectively. Combined with the stepwise regression method, the characteristic bands were substituted into the spectral index to determine that there were three characteristic spectral indices for Mg2+, there were two characteristic spectral indices for salt content, and there were one characteristic spectral index for Na++K+, SO2-4 and Ca2+, respectively. The R2 of model for watersoluble salt ions content based on the characteristic bands and characteristic spectral indices was increased by 5867%, and the RMSE was decreased by 2460%, of which the maximum R2 was SO2-4 (0.74), RMSE was 0.47g/kg. 〖JP〗The model of SVM based on the characteristic bands and characteristic spectral indices combined had a significant improvement in the prediction than that merely based on the characteristic bands, for example, the average relative analysis error (RPD) was increased by 110.27%, the R2 was increased by 37.54% and the RMSE was decreased by 4012% in the training set, the R2 was increased by 5604% and the RMSE was decreased by 3939% in the verification set. The results showed that the RPD of SO2-4 reached 3000, which showed a good prediction ability. The model of salt content and Mg2+ had good quantitative prediction ability which can be used for assessment or correlation prediction, respectively. The SVM models of Na++K+ and Ca2+ had the ability to distinguish between high and low values. 