Exposure of foods to ultraviolet (UV) radiation during processing, storage, and retail display can result in quality deterioration, reduced shelf life and nutritional value, and potential food safety issues. The use of UV-blocking food packaging is an effective strategy to minimize these harmful effects. Carbon dots (CDs) are a class of carbon-based nanomaterials that have emerged as promising candidates for enhancing the UV-blocking performance of biopolymer-based films and coatings. Their unique advantages of excellent UV absorption ability combined with their low toxicity, biocompatibility, and facile production from sustainable precursors make CDs superior alternatives to traditional UV-blocking agents. Incorporating CDs into biopolymers can significantly enhance UV protection without compromising the transparency of the packaging, thereby maintaining the visual appeal of the packaged product. In addition to UV protection, CDs confer multifunctionality to packaging systems by imparting antioxidant, antimicrobial, and pH-responsive properties, thereby meeting the demand for sustainable and intelligent packaging solutions. These advancements not only protect food from photodegradation but also address broader food safety issues through their active and responsive functions. This review provides an in-depth exploration of the role of CDs as UV-blocking agents in sustainable food packaging. It highlights their mechanisms of action, the advantages they offer over conventional materials, and their contribution to the development of multifunctional and eco-friendly packaging systems.