Abstract: Using historical synoptic data,the surface observation data of Guangzhou,the data in the Yearbook on Tropical Cyclones of P.R.China,and NCEP/NCAR reanalysis data of geopotential height,vertical velocity from June to September over the years 1983 to 2004,and defining three days or more in succession with daily maximum temperature over 35℃ as a process of high temperature weather,this work analyzes the relationship between the activity of tropical cyclones and the disastrous high temperature weather in Guangzhou.The result shows that disastrous high temperature weather in Guangzhou is closely related to the outer circulation of tropical cyclones,and high temperature weather over 37℃occur mainly when tropical cyclones move in the range from 400 to 1600 km southeast or south to Guangzhou.Furthermore,the rapid temperature increase with downdraft resulting from tropical cyclones is the major factor inducing disastrous high temperature weather in Guangzhou when the city is controlled by the subtropical high.