Achieving high color rendering index (CRI) and luminous stability in single-structured Ce:YAG phosphor ceramics (PCs) is crucial for high-power white light-emitting diodes or laser diodes (LEDs/LDs). However, cyan valley and insufficient red component of the Ce:YAG emission spectra significantly limit their real applications. In this work, a series of Ce,Mn:Y₃(Al,Sc)₂Al₃O₁₂ (Ce,Mn:YSAG) PCs were fabricated by the vacuum sintering, and an efficient spectral regulation was realized for full-color lighting. The cyan valley was filled by blue-shifted emission peak of Ce³⁺ via Sc³⁺ doping. The orange-red emission around 580 nm was effectively supplemented via Mn²⁺ doping. Particularly, the CRI of Ce,Mn:YSAG increased from 56.4 to 85.8 with a 52% increment compared with Ce:YAG under high-power LED excitation, and the operating temperature was stable at about 50 ℃ under long working time. Meanwhile, the CRI values of 80.9 could still be obtained in PC based white LDs. These results indicated that Ce,Mn:YSAG PC with excellent CRI and luminous stability is an extremely promising color convertor for high-power white LEDs/LDs.