Because of the instability of the thermoregulatory center and poor peripheral circulation, newborns are prone to change with the outdoor temperature, and when the external temperature is low or the package is insufficient, the body temperature will easily decrease and manifest as cold extremities. Newborn babies with cold hands and feet are not relieved even if they are given good warmth, or if they are accompanied by low milk intake, poor response and weak crying, they need to be alerted to the possibility of other combined diseases, such as infection, hypoglycemia, low thyroid function and insufficient feeding. In this case, you need to take your baby to the neonatal unit of the hospital in time to get a clear diagnosis and give symptomatic treatment, and if necessary, you may need to put it in the incubator to keep it warm. Newborn baby body surface area is relatively large, subcutaneous fat is thin, more heat dissipation, indoor temperature should be slightly higher, the general temperature at 22 ℃ -26 ℃, humidity at 55% -65% more appropriate.