If hunger occurs in the early hours of the morning but blood glucose increases, this condition needs to be considered as the phenomenon of Sumuje. Diabetic patients may experience hypoglycemia during treatment, especially at night, and some may experience hypoglycemia followed by reactive hyperglycemia, resulting in early-morning hunger but high fasting blood glucose, which is called Sumuje phenomenon. This phenomenon is mainly due to nighttime hypoglycemia, the body through the negative feedback regulation mechanism, so that the secretion of hormones that have the effect of elevating blood glucose increases, resulting in a rebound increase in blood glucose in the early morning. For diabetic patients who experience the Sumuje effect, they should pay attention to nocturnal hypoglycemia and adjust the time of using hypoglycemic drugs and insulin and the dosage before bedtime. Patients are advised to seek prompt medical attention for a definitive diagnosis.