Purpose <p>Soil compaction poses a significant threat to agricultural productivity. The application of industrial and agricultural wastes as soil amendments offers a promising strategy for its mitigation. This study investigated the individual and combined effects of iron tailings (an industrial byproduct) and maize straw (an agricultural residue) on soil compression characteristics.</p> Materials and methods <p>A laboratory incubation experiment employing a completely randomized factorial design was conducted, with iron tailings applied at 0%, 5%, 10%, and 15%, and maize straw at 0%, 0.5%, 1%, and 1.5% of the air-dried soil mass. Soil compression parameters—pre-compression stress (σ_p), compressibility coefficient (Cc), and recovery coefficient (Rc)—were determined using uniaxial confined compression tests.</p> Results and discussion <p>Iron tailings application significantly increased sand content (Sand) but decreased soil organic carbon (SOC), leading to reduced σ_p and a non-linear effect on Rc. In contrast, maize straw incorporation significantly increased SOC, resulting in enhanced Rc and an initial increase followed by a decrease in σ_p. The Cc was primarily reduced by iron tailings addition, with no significant effect from straw. Variation partitioning analysis and structural equation modeling revealed that Sand was the dominant driver of σ_p and Cc, while SOC governed Rc.</p> Conclusions <p>The combined application of 5% iron tailings and 1% maize straw was identified as the optimal treatment, effectively balancing the amendments’ effects to yield higher σ_p and Rc alongside a lower Cc. These findings demonstrate the synergy between iron tailings and maize straw in improving soil compression characteristics, offering a sustainable strategy to mitigate soil compaction through waste co-utilization.</p>