Steel slag is a typical solid waste from the metallurgical industry. Its use in cement-based materials is severely limited because free oxides cause poor volume stability. Carbonation technology is applied to react CO₂ with reactive components in steel slag. Stable minerals such as calcite are formed. The volume stability of steel slag is therefore significantly improved, and CO₂ is mineralized and stored. The carbonation mechanism was analyzed from the perspective of producing steel-slag-based construction materials by carbonation treatment. The effects and applications of carbonation treatment on drying shrinkage, frost resistance, and chloride ion penetration resistance, and sulfate attack resistance of steel-slag-based construction materials were systematically summarized. Finally, based on the current state of research, existing problems were identified and improvement strategies were proposed. The rational utilization of steel slag as a secondary resource is thereby promoted, and the dual-carbon goals of the construction materials industry are supported.