In this paper, the lakeside oasis of Bosten Lake was taken as the study area, the contents of main soil salt ions (HCO-3, Cl^-, SO₄^2-, Ca²⁺, Mg²⁺, Na⁺+K⁺) were measured, soil hyperspectral reflectance, fractional differential spectral transformation, and 2D soil indexes such as RSI, DSI and NDSI were obtained, and then the estimation models of soil salt ion contents were constructed based on the geographically weighted regression (GWR) model. The results showed that the feature bands of Na⁺+K⁺were concentrated in 468-724 nm and 1 182-1 539 nm under the differential spectral transformation, and the feature bands of 2D soil indexes were concentrated in the near-infrared band (1 742-2 395 nm). GWR model based on RSI feature band optimization estimated Na⁺+K⁺ content well, in which the modeling set R² was 0.94 and RMSE was 0.22, the validation set R²was 0.74 and RMSE was 0.19. The optimal band of SO₄^2- content in order 1.2 was 469-636 nm, in which the modeling set R² was 0.91 and RMSE was 0.02, the validation set R² was 0.75 and RMSE was 0.33. The preferred feature bands of Ca²⁺ and Mg²⁺ were mainly concentrated in the near-infrared band (912-2 340 nm). The modeling effect of the near-infrared band with Cl^- content in the first order was better, the modeling set R² = 0.74, RMSE = 0.03, verification set R² = 0.93, RMSE = 0.11. The accuracies of GWR model of Na⁺+K⁺, SO₄^2-and Cl^- with higher contents were higher than those of Ca²⁺ and Mg²⁺ with lower contents.