Abstract: A rhizobag experiment to investigate the dynamics of pH and salt ions in the rhizosphere and bulk soils was conducted on calcareous salt-affected soils using four salt-tolerant forage species in the Yin Da irrigation district, Yongdeng County of Gansu province. The pH, EC and concentrations of six major salt ions in the soils of tested forage species decreased with an extension of incubation time. There was a significantly lower pH in rhizosphere soils than in corresponding bulk soils during the growth period of all tested plants, such as Xinjiangdaye (Medicago sativa cv. Xinjiangdaye), Zhonglan No.1 (M.sativa cv. Zhonglan No.1), Sesbania cannabina and Puccinellia chinampoensis. EC was higher in rhizosphere soils than in bulk soils for all tested plants after a 90-day growth period. The distribution of salt ions in the rhizosphere and bulk soils showed different change trends at different incubation times. Ca²⁺ and Mg²⁺ were enriched in the rhizosphere soils at different growth stages of all tested plants except Xinjiangdaye at the 90-day growth stage. At the 60-day growth stage, K⁺ concentration in the rhizosphere soils of S. cannabina decreased, but then increased at subsequent growth stages. For the other three forage species, K⁺ was in deficit in the rhizosphere soils. Na⁺ and Cl^- concentrations increased in the rhizosphere soils at different growth stages for all tested plants except Xinjiangdaye and Zhonglan No.1 at the 90-day growth stage. There were significant differences in six major salt ions between the rhizosphere and bulk soils for all tested plants at the same growth stage. The Na⁺/Ca²⁺ and Na⁺/Mg²⁺ showed a decreasing trend with an extension of incubation time. This indicated that the deficit of Na⁺ in the soils was more profound than those of Ca²⁺ and Mg²⁺, and that Na₂SO₄ and MgSO₄ were enriched in the rhizosphere soils of Xinjiangdaye, while NaCl was enriched in rhizosphere soils of the other three forage species.