Sweating on waking up may be caused by physiological phenomena, low blood sugar, hyperthyroidism and other reasons. 1. Physiological phenomenon: it may be caused by the weather is too hot, the blanket is too thick, etc., there can be the phenomenon of waking up sweating. This is a physiological phenomenon and generally does not require special treatment. 2. Hypoglycemia: It may be caused by drugs, heredity and other reasons. Patients often have tremor, palpitations and anxiety, as well as sweating and hunger, which are mainly caused by sympathetic activation. 3. Hyperthyroidism: It is mainly caused by intense mental stimulation, heredity, and excessive iodine intake. Patients may experience abnormal metabolic excitement, which may lead to sweating upon waking. It is recommended that patients who sweat when they wake up go to the hospital in a timely manner and follow the doctor’s instructions for treatment to avoid delaying the condition.