Patients with diabetes are prone to concurrent infection. The mechanism of concurrent infection is related to factors such as hyperglycemia and weakened defense function. The infections of patients with diabetes include general and special infections. General infection includes infections in the respiratory system, urinary system, hepatobiliary system, and skin mucosa. Meanwhile, special infection includes invasive otitis externa, nasal mucormycosis, necrotizing fasciitis, and emphysema infection. Patients with special infections also have a higher mortality rate than those with general ones. Complicated infection with diabetes is difficult to treat and has poor prognosis. Therefore, a patient requires active treatment once infected with this infection.With the increased prevalence of diabetes, related acute and chronic metabolic disorders and various complications, such as complications in the blood vessels and nerves, also increase significantly, thereby posing the challenges for the overall survival of patients with diabetes. Patients with diabetes suffer from T-lymphocyte and neutrophil dysfunction, decreased humoral immune function, oxidative-antioxidative imbalance, and defects in opsonization and phagocytosis [1]. Patients with diabetes are significantly prone to infection, which is difficult to control. Many specific infections are common in patients with diabetes, whereas some infections occur almost exclusively in patients with diabetes. This article reviews the progress in clinical research on complicated infection with diabetes.