Abstract: As a non-ferrous metallurgical slag, nickel slag has a potential recycling value with an iron grade of up to 40%. The iron in nickel slag is mainly ferrous silicates, making it difficult to be extracted effectively. The reasonable use of nickel slag, the current research hotspot, is of great significance to the sustainable and green development of the industry. In this paper, a comprehensive analysis of iron resource recovery technology for nickel slag was conducted. Focusing on the existing problems in the iron extraction process from nickel slag, it was proposed to add calcium to adjust the nickel slag type during the nickel smelting process, thereby reducing the smelting temperature and transforming iron olivine to calcium ferrate. This method can reduce the difficulty of subsequent iron extraction and realize the comprehensive utilization of high-value resources in term nickel slag.