Diabetes mellitus(DM)is a chronic metabolic disease characterized by persistent hyperglycemia and rapidly increasing. The ocular surface microbiota(OSM)consists of microbial communities that colonize the eye surface, mainly bacteria, and perform an important role in maintaining ocular health. Hyperglycemia creates a favorable microenvironment for the OSM, leading to an imbalance of the microflora. However, unpredictable changes in OSM are strongly associated with dry eye disease, corneal neuropathy, and infectious ocular surface diseases in environmental changes. In recent years, next-generation sequencing technology has been applied to detect the OSM and confirm that the eye microbiome is closely related to DM. Research indicates that dysbiosis of the OSM plays a critical role in the onset and progression of DM-related ocular surface diseases. This review investigates the correlation between OSM and patients with DM. Moreover, we provide a reference for the occurrence and development of diabetes-related ocular surface diseases and their treatment.