Diabetes mellitus (DM) is a global health crisis that not only affects blood glucose regulation but also significantly impacts various organs and body systems, including immune function. One of the most concerning complications of DM is an increased susceptibility to infections, particularly respiratory infections. These infections, ranging from pneumonia to viral respiratory infections such as influenza and tuberculosis (TB), and fungal infections like aspergillosis, tend to be more severe in diabetic individuals, leading to prolonged illness, increased hospitalisation, and mortality. This article provides a comparative analysis of the mechanisms through which diabetes impacts respiratory infection susceptibility, explores the types of respiratory infections that are most common in diabetic patients and offers an in-depth look at the clinical consequences of these infections. Furthermore, we discuss innovative approaches to managing and preventing respiratory infections in individuals with diabetes, including novel vaccines, precision medicine, and integrated care models. © 2025 Elsevier B.V., All rights reserved.