Abstract: Carbon dots (CDs) have great potential as luminescent materials in the fields of sensing, information security, biomedicine and so on. However, it is still a great challenge to prepare CDs based room temperature phosphorescence (RTP) materials with stable optical properties, long phosphorescence life and high quantum efficiency. Immobilizing CDs on SiO₂ matrix to construct the CDs/SiO₂ composites, which can utilize the synergy between CDs and SiO₂. It not only can improve the dispersion of CDs to achieve stable solid-state fluorescence of CDs, but also can generate stable triplet excitons to achieve long-life phosphorescence of CDs. The RTP CDs/SiO₂ composite is of great significance for expanding the phosphorescent application field of CDs-based composites. In this paper, the preparation methods, properties and applications of phosphorescent CDs/SiO₂ composites in recent years were reviewed. The existing problems in the development of phosphorescent CDs/SiO₂ composites were summarized, and the development direction of CDs/SiO₂ composites was prospected.