Abstract: The saline-sodic soils of the Songnen Plain exhibit poor physicochemical properties, including high pH and electrical conductivity (EC), which severely restrict crop growth and constrain regional agricultural production. Although various methods for improving saline-sodic drylands have been proposed, their effectiveness varies. Iron tailings, a byproduct of the steel industry, have similar properties to sandy soils. However, the improvement effect and mechanism of iron tailings as an amendment in saline-sodic dryland have not been thoroughly studied. In this study, five treatments were established, including a control (CK), control + organic cow manure (CK+CM), and three iron tailings application rates (200 t·hm⁻², 400 t·hm⁻², 600 t·hm⁻²) based on CK+CM. Systematically investigated the effects of iron tailings addition on soil physicochemical properties and agronomic and yield related traits of maize. The results showed that, based on the application of organic cow manure, the addition of iron tailings significantly reduced soil pH and electrical conductivity, improved soil physical structure, especially at the high application rate of 600 t·hm⁻², where soil bulk density decreased significantly, indicating a marked improvement in soil structure that is more favorable for crop root growth. Iron tailings treatment also promoted maize seedling emergence, plant height, and stem diameter. The maize yield was significantly increased in the addition of 600 t·hm⁻² treatment, reaching 3824 kg·hm⁻², which was 151% more than CK and 60.7% more than CK+CM. This study indicates that iron tailings, as a low-cost and effective soil amendment, have great potential for improving saline-sodic drylands and provide important scientific support for the sustainable utilization of saline-sodic drylands.