Steel slag, a typical solid waste product of the metallurgical industry, contains free calcium oxide (f-CaO) and free magnesium oxide (f-MgO), which can cause volume expansion when directly applied to cement-based materials, severely limiting its recycling applications.Carbonation technology reacts CO? with the active components in steel slag to form stable minerals such as calcite, which not only significantly improves the volume stability of steel slag but also enables CO? mineral sequestration. This paper focuses on the preparation of steel slag-based building materials through carbonation treatment, analyzes the carbonation mechanism, and comprehensively reviews the effects and applications of carbonation treatment on the drying shrinkage, freeze-thaw resistance, and chloride ion permeability of steel slag-based building materials. Finally, the paper proposes further improvements to address the current research status and existing issues, contributing to the rational use of steel slag as a secondary resource and promoting the "dual carbon" goals of the building materials industry.