Abstract: Graphene quantum dots (GQDs) are a new type of fluorescent carbon material characterized by a lateral size of less than 30 nm and fewer than 10 layers. Due to their unique properties and broad application prospects, GQDs have attracted extensive attention. In this paper, we introduce the unique structural, electrical, and optical properties of GQDs, summarize the main preparation methods, and detail their applications in new energy, catalysis, sensing, biomedicine, and environmental remediation. Finally, we briefly discuss the research progress on standard reference materials for GQDs. Future research on GQDs mainly focuses on improving photoluminescence quantum yield and production output, as well as expanding application ranges and developing standard reference materials. With advances in new material design concepts and the continuous development of quantum technology, GQDs and their standard reference materials are expected to demonstrate unique advantages and application value in more fields.