If a diabetic patient’s blood sugar is well controlled, the urine will have no noticeable taste. If the blood sugar is not well controlled, the urine will have a sweet smell. If the diabetic patient’s condition is not well controlled, not only urination will smell bad, but even breathing and sweating will smell bad. When a diabetic patient’s condition is severe and the patient develops ketoacidosis, the breath will smell like rotten apples. Diabetic patients with bad odor in urine should consider poor control of diabetes and be careful of complications of diabetes, such as diabetic ketoacidosis, diabetic nephropathy, urinary tract infections, etc., and should be examined and treated in a timely manner. Usually patients should take measures to control blood sugar, keep blood sugar at a stable level, control diet reasonably, ensure appropriate amount of exercise, improve body resistance, do self-monitoring, and if abnormalities are found, actively seek medical attention to avoid serious complications.