Abstract: This study comprehensively analyzes the natural distribution characteristics of saline-alkali soils in China. By integrating industry standards and specifications from field such as agriculture, ecology, engineering, it systematically reviews the determination methods for water-soluble salt indicators, acidity/alkalinity indicators, physical indicators, and nutrient indicators. Furthermore, it summarizes the grading systems adopted across different regions and industries. With a total area of approximately 3.69×10⁷ hm², saline-alkali soils in China are primarily distributed across five major regions (such as Northeast China, coastal zones, and North China) and are categorized into six primary types, including chloride and soda salt soils, representing significant potential resources for agricultural utilization. Core evaluation indicators comprise total dissolved solids (TDS), pH value, and sodium adsorption ratio (SAR). However, certain discrepancies exist in the determination methods across different sectors (e.g., agricultural standards versus engineering standards). The classification standards for saline-alkali soil vary regionally, for instance, in coastal regions, soil with TDS>6.0 g/kg is classified as saline soil, whereas in the desert regions of Northwest China, the threshold is TDS>10 g/kg. Establishing a unified classification system is crucial for effective remediation and management of saline-alkali soils. The forthcoming recommended national standard, Classification and Grading of Saline-Alkali Soil for Agricultural Use, incorporates key indicators such as electrical conductivity of saturation paste extract (ECe) and exchangeable sodium percentage (ESP) to enable adaptable soil quality assessment and management. In addition to chemical indicator systems, remote sensing interpretation and other technologies can facilitate the development of region-specific remediation strategies. A comprehensive understanding of the classification, grading, and evaluation indicators of saline-alkali soils is essential for conducting regional surveys and assessments, as well as for selecting candidate materials and characteristic indicators in the development of soil standard reference substances.