Low blood sugar level can be roughly divided into two cases. One is the normal level of low blood sugar, when the blood sugar has been low, but the blood sugar level has not reached the level of hypoglycemia, this situation is mostly related to irregular diet, eating too little or not eating after strenuous activities, generally can be relieved by eating in time. Another situation is caused by certain diseases, such as insulin resistance in type 2 diabetes, which often causes hypoglycemia before lunch or dinner, fasting hypoglycemia caused by insulinoma, and hypoglycemia caused by low glucocorticoid level in adrenal insufficiency. On the one hand, the hypoglycemia caused by these diseases should be corrected in time, and on the other hand, reasonable diagnosis and treatment should be made according to the different conditions, and the original disease should be dealt with, such as improving insulin resistance in type 2 diabetes, and timely surgery in insulinoma after clear diagnosis.