Diabetes mellitus (DM) is a condition of abnormal carbohydrate metabolism, leading to persistent hyperglycemia. It is defined as a fasting blood glucose over 7.0 mmol/L, a 2-hour plasma post-meal of 11.1 mmol/L, or HbA1C values over 6.5% (48 mmol/L). DM affects almost 600 million people globally with an annual cost of around three trillion US dollars. These data indicate that DM is a global health burden that warrants attention. Complications of DM include nephropathy, retinopathy, neuropathy, and cardiomyopathy. DM-induced hyperglycemia causes oxidative stress, inflammation, endothelial and mitochondrial abnormality, and subsequently, cardiomyopathy. Hyperglycemia stimulates many signaling pathways including polyol, and hexokinase, resulting in the formation of vascular endothelial lesions, free radicals and carbonyl anions, transforming growth factor-β1, fibronectin, and nuclear factor kappa-B, which increase fibrosis and inflammation in the myocardium. All of these pathological processes lead to defective vascular permeability and hypoxia in cardiac tissue, ischemia, and eventually heart failure, and sudden cardiac death. The onset of diabetic cardiomyopathy could be delayed with a healthy lifestyle (balanced diet, physical activity, sleep, low stress, non-smoking). GLP-1 receptor agonists with or without SGLT2i are beneficial additions for the treatment of diabetic cardiomyopathy.