This study explores the influence of multi-component solid waste under separate grinding processes on the performance of cementitious materials. Multiple technical schemes were designed to investigate the variation patterns of cement strength during the synergistic application of multi-component solid waste. The results indicate that fly ash exhibits significant grinding-aid effects when its dosage <10%, with a specific surface area of 500~550m2/kg and SO3 content of 2.1%~2.5%. The composite blending of fly ash with ultra-fine powder (prepared from refined steel slag and granulated blast furnace slag at a 1:1 ratio) demonstrates superior 3d and 28d cement strengths compared to fly ash blended with slag powder, suggesting a mutual activation effect among fly ash, refined steel slag, and slag. The utilization of fly ash-based multi-component solid waste in cement and concrete production not only addresses the challenge of low solid waste utilization but also promotes green and low-carbon development in the building materials industry.