The main causes of sweating in bed are: environmental factors, autonomic dysfunction, tuberculosis, hyperthyroidism and so on. 1. environmental factors: sleeping environment temperature is too high, or clothing bedding is too thick, affecting the body heat dissipation, will make the body heat dissipation is not good, leading to sleep all over the body sweating situation. 2. autonomic nervous system dysfunction: due to anxiety, stress and other reasons, peri-menopausal hormone secretion level decline, etc., there will be autonomic nervous system dysfunction, sympathetic nerves are overly excited, so that the body gland secretion increases, there will be sleeping sweating symptoms. 3. Tuberculosis: If you have tuberculosis and are in the active stage of the disease, Mycobacterium tuberculosis will secrete toxins in your body, leading to low-grade fever and night sweats, which will cause you to sweat all over your body when you sleep. 4. Hyperthyroidism: With hyperthyroidism, the body secretes more thyroid hormones, the metabolism level increases, and more heat is produced, which will lead to the symptoms of sweating all over the body while sleeping, and may also be accompanied by symptoms of panic and shaking hands. If the above symptoms occur, it is important to consult a doctor in a timely manner after eliminating the environmental factors, so as to avoid delaying the condition.