9-month-old baby’s normal body temperature is less than 37.4 ℃ is considered normal, the body temperature in the period of 37.4-38.1 ℃ is low fever; body temperature in the period of 38.1-39.1 ℃ is moderate fever; body temperature greater than or equal to 39.1 ℃ is high fever. 9-month-old baby in daily life, the body temperature is mostly below 37.4 ℃, but if the environmental temperature is too high, or because the baby drink water But if the ambient temperature is too high, or because the baby drink less water, and parents to the baby wear too much clothing, the temperature may be slightly higher than the normal body temperature, the temperature may reach 37.5-37.6 ℃, this situation does not belong to the disease caused by the appropriate amount of lowering the ambient temperature to drink more water, reduce the clothing wear, the baby’s body temperature can be receded to normal. This is the cause of heat dissipation, can be appropriate to drink more water, the general body temperature can be back to normal.