Background and aims <p>Red mud is a strongly alkaline solid waste with potential ecological risk problems. However, there is less research on soil ecological problems caused by red mud, and there is a lack of research on corresponding remediation methods.</p> Methods <p>In this study, we used red mud to contaminate agricultural soils to investigate the effects of alkali stress on the soil-wheat-microbial system. The effects on the soil environment and wheat growth were explored by applying inorganic acids (nitric, hydrochloric, and sulfuric acids) to the contaminated soil to regulate the rhizosphere soil microbial community.</p> Results <p>The results showed that red mud alkali stress reduced soil fertility, inhibited wheat growth, and reduced rhizosphere microbial diversity. Application of inorganic acids significantly increased microbial diversity, altered the community structure, and induced a more stable correlation network in response to alkali stress. The abundance and expression levels of functional bacteria (such as <i>Sphingomonas</i> and <i>Mesorhizobium</i>) and taxa (including Nitrification and Nitrogen fixation) involved in nitrogen and phosphorus cycling were enhanced, contributing to improved soil fertility. This provided more nutrients for wheat growth and alleviated wheat growth inhibition under an alkali stress environment.</p> Conclusion <p>Application of inorganic acids to red mud-contaminated soil improved the soil environment and promoted wheat growth by regulating the rhizosphere soil microbial community. In large-scale applications, strict control of acid dosage and post-remediation soil pH levels is required. These findings enhance the understanding of the hazards of red mud and provide ideas for remediation and management of red mud pollution.</p> Graphical Abstract <p></p>