The iron and steel industry is a cornerstone of the national economy, yet its production process generates a massive amount of solid waste, among which iron and steel slag is the primary by-product. For a long time, the stockpiling and landfilling of this slag have not only occupied vast land resources but also posed potential threats to the soil, water, and atmosphere due to heavy metal ions in leachate and dispersion of dust. However, steel slag is a secondary resource awaiting development, which is rich in valuable elements such as calcium, silicon, iron, aluminum, magnesium, and manganese, as well as rare metals like vanadium and titanium. Main phases of steel slag include dicalcium silicate, tricalcium silicate, and calcium ferrite. Resourcezation potential of steel slag comes from two aspects. On one hand, technologies such as magnetic separation, gravity separation, or reduction roasting can recover iron and rare metals. On the other hand, high calcium and silicon content endows it with the potential to substitute for natural mineral resources. Achieving efficient recovery of valuable elements from steel slag and comprehensive application of the overall material is crucial for promoting green, circular, and low-carbon development of the iron and steel industry. This review systematically summarized physicochemical properties of steel slag, focusing on technical principles and research progress in recovering major valuable elements like iron, calcium, and silicon, as well as rare elements such as vanadium and titanium. Simultaneously, it comprehensively outlined current status of steel slag utilization in fields such as building materials, environmental remediation, and agriculture. Finally, it analyzed current technological challenges and provided an outlook on future research directions, offering a theoretical reference and technological pathways for high value resources utilization of steel slag.