Hypothermia is generally referred to as low fever between 37 degrees and 38 degrees, and there are many causes of hypothermia. Short-term hypothermia is usually directly related to infectious diseases, or other diseases that are not serious. The more common infectious diseases are tuberculosis, some chronic urinary tract infections that lead to hypothermia, but those with joint pain should pay attention to rheumatoid arthritis, connective tissue disease, etc. There are also some physiological hypothermia, such as a small range of hypothermia in pregnant women. The hypothermia is caused by the weakness of the thermo-center to regulate exogenous hyperthermia during the hot summer months, but it is not pathologically significant. It is important to note that in the identification of the etiology of hypothermia, the majority of prolonged hypothermia is organic in nature, in which infection is predominant, because the duration of prolonged hypothermia is long, and a comprehensive analysis should be made according to the combined symptoms of hypothermia in various parts of the body.