Based on the hydrochemical data of shallow groundwater in Yinchuan Plain, the total dissolved solids (TDS), pH and main ions were analyzed using statistical methods, Pipe-trigram, Gibbs model, and correlation analysis to study the formation mechanism of the shallow groundwater. The results showed that: (1) The spatial variability of TDS, Cl^-, SO_2^-4 , K^+, Na^+ and Mg^2+ was relatively large, whereas the spatial variability of Ca^2+ and HCO_3^- is relatively small. (2) The degree of mineralization of shallow groundwater could be divided into three stages: the first stage consisted primarily of HCO_3-SO_4 water or HCO_3-Cl water stage with TDS<1 g·L^-1; the second stage was mainly characterized by SO_4-Cl and SO_4-HCO_3 water, with TDS generally ranging from 3 to 6 g·L^-1 and exceeding 6 g·L^-1 in some areas; the third stage was characterized by Cl-SO_4 and Cl-HCO_3 water, with TDS generally ranging from 3 to 10 g·L^-1 and reaching 10 g·L^-1 or higher in some areas. (3) The degree of mineralization of shallow groundwater was primarily controlled by evaporation, concentration, and rock weathering, with additional influence from cation exchange. Regarding the contribution to the degree of mineralization, the water chemical components followed a descending order of Na^+, Cl^-, SO_2^-4 , Mg^2+, Ca^2+, and HCO_3^-1. For TDS<1 g·L-1, the mineralization of shallow groundwater was mainly influenced by the dissolution of rock salt and carbonate. However, after TDS exceeded 3 g·L^-1, the contribution of gypsum and magnesium sulfate dissolution to the mineralization of shallow groundwater increased.