Abstract: Against the backdrop of intensifying global climate change and increasing constraints on water resources, soil salinization has become a critical environmental issue restricting sustainable agricultural development and the secure utilization of cultivated land resources. China possesses extensive and diverse saline-alkali lands which, as important strategic reserve arable land resources, are of great significance for ensuring national food security through their efficient reclamation and rational utilization. Based on recent domestic and international research achievements in saline-alkali land remediation, this paper systematically reviews the research progress of core remediation technologies, including water-salt regulation engineering technology, improvement of soil physicochemical properties, and biological-ecological restoration. Particular emphasis is placed on analyzing the mechanisms, applicable conditions, and practical limitations of different remediation technologies. The results indicate that saline-alkali lands in China are jointly influenced by multiple factors, including climate, hydrogeological conditions, and anthropogenic activities, four representative regions were selected for comparative analysis: soda saline-alkali soils in the Songnen Plain of Northeast China, coastal saline-alkali soils in eastern coastal areas, sulfate-chloride saline-alkali soils in arid and semi-arid regions of central and western China, and saline-alkali soils in the Hetao Plain. Significant differences exist in the dominant limiting factors and water-salt transport mechanisms among these regions, making it difficult to adopt a unified technical remediation model. Water-salt regulation engineering technology mainly relies on salt leaching through irrigation and drainage, drip irrigation under mulch, physical barriers, and agronomic tillage practices, which effectively achieve “salt removal with water movement” and suppress salt accumulation. However, these approaches are often associated with high water consumption, risks of secondary salinization, and elevated engineering maintenance costs. Chemical amelioration primarily depends on calcium-based amendments, organic conditioners, and novel functional materials, which improve soil physicochemical properties through ion exchange and structural reconstruction. Nevertheless, long-term application may introduce environmental risks and economic burdens. Biological-ecological restoration promotes the reconstruction of soil ecological functions through salt-tolerant plants, microorganisms, and organic matter regulation. Despite these advances, current remediation systems still face major bottlenecks, including the difficulty of simultaneously achieving salt tolerance and high crop productivity, as well as the lack of standardized monitoring and evaluation systems based on the electrical conductivity of saturated soil paste extract. Based on regional dominant limiting factors and water-salt regulation engineering technology mechanisms, this study further proposes a regionally differentiated integrated remediation framework featuring coordinated “engineering-chemical-biological” approaches. Future saline-alkali land remediation should place greater emphasis on the synergistic integration of water-saving and salt-control strategies, the development of green and low-consumption amendment materials, and innovation in agricultural engineering equipment. Particular attention should be devoted to overcoming the limitations of conventional high-energy-consumption agricultural machinery in deep straw burial operations, accelerating the development of specialized combined-operation machinery and green engineering technology systems suitable for saline-alkali land remediation, and establishing precise monitoring networks integrating the Internet of Things and multi-source remote sensing technologies, thereby promoting the development of saline-alkali land remediation in China toward greater efficiency, lower energy consumption, and long-term sustainability.