Carbon dots is a new type of fluorescent carbon nanomaterial, which the diameter is generally less than 10 nm, has the advantages of self-fluorescence, remarkable biocompatibility, easy modification, low cost and so on, has a broad application prospect in the biomedical field. Due to the unique barrier of the eye, conventional drugs have a short residence time and poor penetration, so the concentration of drugs that can reach the lesions through local eye drops is limited, and for what to increase the frequency of administration to maintain efficacy. Up to now, the treatment of posterior eye diseases, such as diabetic macular edema (DME), choroidal neovascularization (CNV) and other diseases still rely on repeated vitreous injection, which is an invasive procedure with potential complications, and need multiple injections, causing a heavy psychological and economic burden on patients. Optimizing the method of ocular drug delivery has always been a hot topic in the field of ophthalmology. Carbon dots have shown excellent application potential in the ocular drug delivery, ocular imaging, and diagnosis and treatment of ocular disease based on its excellent characteristics. This review will systematically introduce the characteristics of carbon dots and the application of carbon dots in the diagnosis and treatment of eye diseases, aiming to provide a comprehensive understanding of the current situation of the application of carbon dots in ophthalmology and provide directions for future research.