Recycled powder (RP) is considered to be a successful low-carbon alternative to ordinary Portland cement (OPC). However, the microstructure and synergistic mechanism of RP multi-component cementitious materials (RP-MCCM) after physical activation are still unclear. The purpose of this study is to study the strength development, hydration and phase structure evolution of MCCM by constructing RP-MCCM. When the content of RP after grinding activation is 30% (C70RG30), its 28 days compressive strength is increased by 7.6% on the basis of non-activation. Compared with the ternary system of RP and FA mixed with 15% (C70RG15F15), its 28 days compressive strength increased by 8.08%. After RP incorporation, the Al-OH is enhanced, the C-O and CO32- bonds peaks become narrower, and the S is evenly distributed, which is beneficial to the increase of the AFt and the CaCO3 content, but weakens the C-S-H and C-A-H phases. In the C70RG15F15 ternary system, CaCO3, Ca(OH)2, and SiO2 nanostructures are tightly bonded together without obvious faults, which improves the structural compactness and strength. RP grinding activation is mainly manifested in surface improvement, internal C-S-H activation and increase of active sites.