High fasting blood glucose should first be clarified as diabetes or transient elevated blood glucose, and then treated according to the specific cause, with medication if necessary. The first step in the development of elevated fasting blood glucose is to clarify whether it is diabetes or not. In the case of some physiologic factors, elevated blood glucose can occur regardless of whether it is diabetes or not. Common physiologic factors include situations such as strenuous activity and emotional excitement. The diagnosis of diabetes can be confirmed if the fasting blood glucose is higher than 7.0 mmol/L on at least two occasions, or if it is accompanied by the typical symptoms of “three more and one less” (i.e., drinking, eating, urinating, and weight loss). Diabetes can also be diagnosed by measuring blood glucose 2 hours after a meal, random blood glucose, and so on. Management of diabetes includes lifestyle improvement and medication. Lifestyle improvement includes dietary control such as low sugar diet, low fat diet, and regular physical activity. Medications such as hypoglycemic treatment with drugs like dagliflozin, gliquidone, metformin and insulin. Elevated fasting blood glucose can be seen in the outpatient clinic, blood glucose review to identify the specific cause, and medication should be applied appropriately according to the doctor’s instructions.