In order to solve the disposal problem of waste stone powder（WSP） generated in the production of manufactured sand， a new strategy was proposed to reuse it as a mineral admixture for concrete. The characteristics of WSP and its influence on the compressive strength and pore structure of concrete were studied， and the carbon emissions reduction benefits brought by the use of WSP were analyzed based on the life cycle assessment method. The results show that although WSP has a higher methylene blue value than ground stone powder（GSP）， it has little influence on the flowability of the mortar. Compared to GSP and fly ash， WSP reduces the compressive strength of low-strength grade concrete， but has a moderate influence on the compressive strength of high-strength grade concrete. WSP as a mineral admixture can effectively reduce carbon emissions from concrete production， and the total carbon emissions of concrete mixed with 20% WSP are reduced by nearly 20%.