Abstract: Silicon quantum dots (SiQDs), as emerging nanoscale semiconductor materials, have attracted extensive attentions in optoelectronic devices and light-emitting diodes (LEDs) due to their excellent photoluminescence and electrolumine scence properties, low toxicity, environmental friendliness, and good compatibility with silicon-based microelectronics fabrication processes. Compared with conventional III-V semiconductor quantum dots, the luminescence characteristics of SiQDs can be tuned and optimized via size control, surface passivation, and doping, demonstrating great potential in various applications. In recent years, researchers have conducted in-depth investigations into the luminescence mechanisms of SiQDs by combining experimental and theoretical approaches. These mechanisms include quantum confinement effects, defect-induced emission, and the influence of surface ligands. Significant breakthroughs have been achieved in enhancing quantum yield and improving emission stability. However, further optimization of the optoelectronic properties of SiQDs and their integration into practical devices remain key challenges. This paper reviews the main synthesis methods, optoelectronic properties, and recent application advances of SiQDs, analyzes critical issues encountered during their development, and discusses possible future research directions.