Abstract: The efficient utilization of coastal saline-alkali land is crucial for ensuring food security and improving the ecological environment in China. Despite facing the dual challenges of freshwater scarcity and soil salinization, the abundant saline water offer new opportunities for sustainable agricultural production in this area. Long-term use of saline water irrigation may bring about a series of adverse effects. Therefore, this paper systematically summarizes the effects of saline water irrigation on soil, crops, and the ecological environment in coastal saline farmland. It comprehensively reviews key technologies, such as saline water quality improvement, safe and efficient irrigation, and stepwise utilization of fresh and saline water. Innovatively, it condenses and expounds on three models: the composite ecological model of salt-tolerant crops with saline water irrigation, the comprehensive management model for saline water irrigation and water-salt regulation, and the synergistic model of photovoltaic, edible fungi, and saline water. Considering the characteristics of water-salt distribution, precipitation and water table in coastal saline-alkali areas, a zoned utilization strategy for saline water is proposed: In severely saline-alkali areas, pioneer halophytes such as Suaeda salsa and Tamarix chinensis are planted. Saline water (with a salinity greater than 5 g∙L⁻¹) is mainly used for irrigation. The freeze-thaw technology is employed to reduce the salt accumulation in the 0−40 cm soil layer over the main root zone. Depending on local conditions, either the “saline water drip irrigation + high ridges + film mulching” model is selected, or the rotation model of edible fungi and vegetables is implemented. In moderately saline-alkali areas, salt-tolerant cash crops like cotton and forage grass are cultivated. Brackish water (with a salinity of 2−5 g∙L⁻¹) is primarily used, with fresh water supplementation during the salt-sensitive growth stages of crops (such as the seedling and bud stages of cotton). Water activation treatment and the stepwise utilization technology of fresh and saline water are applied. Additionally, the synergistic model of photovoltaic-edible fungi-saline water can be adopted to enhance sustainability. In lightly saline-alkali areas, lightly and moderately salt-tolerant food crops such as wheat and corn are grown. Fresh water is mainly used for irrigation, with brackish water supplemented during the salt-tolerant growth stages (for example, after wheat booting stage and the corn large bell-mouth stage). The smart irrigation scheduling approach based on the Plant Water Deficit Index (PWDI), precisely controls the irrigation volume and time for fresh and brackish water, in accordance with the soil water, salt and crop growth conditions, thereby optimizing water use efficiency. Future research should focus on strengthening the study of the impact of saline water irrigation on regional water resources and salt balance, deepening the simulation of regional water-salt movement models, exploring the coordinated development with the ecosystem, and promoting the integration of multiple technologies and smart management, to provide a theoretical foundation and technical support for the sustainable development of coastal saline-alkali land in China.