Abstract: The mechanism underlying the effects of cold air on hypertensive disorders was investigated in an experimental study examining blood pressure and biochemical indicators. Zhangye, a city in Gansu Province, China, was selected as the experimental site. Health screening and blood tests were conducted. 30 cardiovascular disease patients and 30 healthy subjects were recruited. The experiment was performed during a cold event during April 26-29, 2013. Blood pressure, norepinephrine (NE), epinephrine(E) and angiotensin II (ANG-II) levels of the 60 subjects were evaluated 24 h before cold air activity, during cold air activity, and 24 h after cold air activity. The change before, during, and after the cold air activity was analyzed. Cold air exposure can cause a significant increase of metabolism and secretion of norepinephrine (NE), epinephrine (E) and angiotensin II(ANG-II) in subjects, Furthermore, the mean value of NE, E, ANG II and the systolic blood pressure still maintained at a high level one hour after the end of the cold air exposure. The impact of cold air exposure on the change of blood pressure was shown in both cardiovascular patients and healthy people, and the effect on the cardiovascular patients lasted longer. Cold air exposure increases blood pressure in cardiovascular disease patients and healthy subjects via the sympathetic nervous system (SNS) that is activated first and which augments ANG-II levels accelerating the release of the norepinephrine and stimulates the renin-angiotensin system (RAS). The combined effect of these factors leads to a rise in blood pressure. This paper discusses preliminarily the possible mechanism for increasing human blood pressure led by cold air.