The yardang strata is the material manifestation of the sedimentary system before the yardang landform developed. It records a large amount of surface process information such as sedimentation processes， environmental evolution， and landform patterns. The physical and chemical analysis of sediments has become an important prerequisite for interpreting its key information. As an important environmental proxy index， the characteristics of easily soluble salts have important significance in interpreting the sedimentary evolution process of the yardang Formation. This paper takes Dunhuang yardang landforms as the research object， and conducts an in-depth discussion on the soluble salt deposition characteristic， environmental proxy indicators and sedimentary environment evolution of its exposed strata. The results indicated that： （1） The dominant ions' composition of soluble salts in yardang sediments is characterized by the combination of Mg{}_{}^{\mathrm{2}+}-Na⁺-Ca²⁺-Cl^--SO{}_{\mathrm{4}}^{\mathrm{2}-}， and the corresponding ion types mainly include Cl-Na type and SO₄-Ca-Mg type. （2） The main ions and the total salt content in the studied profiles have significant vertical cycle variation characteristics， mainly dominated by the alternating changes of sulfate and chloride salts， both of which play a decisive role in controlling the deposition of yardang soluble salts. （3） Environmental proxies such as Mg²⁺/Ca²⁺ and Cl^-/SO{}_{\mathrm{4}}^{\mathrm{2}-} have certain limitations in the differentiating of yardang environmental changes， indicating that yardang strata were not entirely developed from stable lacustrine deposition. （4） The yardang formation is the result of alternate deposition of various materials formed under different sedimentary environments and dynamic mechanisms， which mainly includes stable lacustrine， lakefront， fluvial， aeolian and alluvial fan's mud flat materials. Among them， lakefront， fluvial and aeolian sediments have similar physical and chemical properties， making it difficult to distinguish in detail and need further study.