Salinity stress exerts a harmful effect on crops and cropping systems by disrupting their physiological processes, leading to a substantial reduction in growth, productivity, and overall quality. Prolonged exposure to high salinity levels can stress affect water uptake, nutrient balance, and metabolic functions, weaken crop resilience, reduce productivity, and compromise the quality of agricultural produce, posing a serious hazard to food security in salt-affected regions. Therefore, adopting a sustainable agronomic strategy is vital for preserving crop yield and quality, especially in the intensified phase of climate change. Selenium is recognized as a trace element for plant growth and development. The application of selenium mitigates various abiotic and biotic stress, including salinity, and is emerging as a climate-smart technology. It can potentially induce salt stress tolerance in numerous crops by upregulating salinity tolerance genes. Seed priming with selenium or its exogenous application improves the germination of seeds, boosts the antioxidant system, enhances photosynthesis, and improves the uptake of water and nutrients in salt-affected soils. Selenium enhances the plant's defense against oxidative stress by stimulating the synthesis of non-enzymatic antioxidants like ascorbic acid, glutathione, and phenolic compounds, as well as enzymatic antioxidants such as superoxide dismutase and catalase. It also promotes the production of osmolytes like proline and glycine betaine for osmotic balance and helps regulate ion homeostasis by maintaining ion compartmentalization and transport, improving mineral nutrition, and supporting crop growth under salinity stress. Hence inclusion of selenium in plant nutrition is a very vital for ensuring sustainable crop management in salt-affected soils globally.