Abstract: Based on the routine datas and the airplane reports of Guiyang airport,the climatic characters and circulation background of low-level windshear of Guiyang airport are analysed,at the same time the wind field characters of low-level windshear are analysed.The result shows that the low-level windshear of Guiyang airport mainly take place in later winter and spring,March and August appear more times.In a day the low-level windshear often take place after 10 oclock at AM,the higher frequency appear in the afternoon.The circulation background of windshear include the cold-front type,high pressure rear type and thermal low pressure type,and the cold-front type is the main circulation background.From the wind field characters,when the ground wind are the South wind and North wind,the low-level windshear will occur,but it appears higher frequency on the north wind conditions.When the low-level windshear take place,the boundary wind are all the South wind,accompany with high wind speed.Before the cold-front type low-level windshear occur,the ground wind turn the South wind to the North wind,but when the ground wind become the North wind,the low-level windshear will occur.When the low-level windshear of high pressure rear type and the thermal low pressure type take place,the ground wind are the South wind.