Drooling during sleep in diabetic patients may be caused by autonomic dysfunction, periodontal disease, craniocerebral disease and so on. 1. Diabetic patients are prone to autonomic dysfunction, increased nerve reflexes lead to increased salivary secretion, so drooling will occur during sleep. 2. Diabetic patients with oral diseases, such as periodontitis, oral ulcers, etc., can be due to excessive secretion of the salivary glands or the corners of the mouth to close the difficulty of drooling during sleep. 3. Diabetic patients with combined craniocerebral disease, cerebral thrombosis, etc., can be due to thrombus compression of the nerves and the mouth and eyes tilted, and even drooling during sleep. Diabetic patients with increased drooling at night should pay attention to the hospital examination to clarify the cause of the disease, according to the cause of the disease to follow the doctor’s instructions for systematic treatment.