On the fundamental of the Coutaque's index of monthly aridity and utilizing the Kppen limit it of the dry steppe climate and wet forest climate in the summer pluvial regions,the examination and revision of the climatic information are conducted.Considering the climatic characteristics of Guangdong,a formula of climatic index of ariditty and wetness has been presented. The aridity and wetness index are computed and analysed with the data of a year,sumer and winter half year,and some year or months in Guangdong.These results are improtant for agriculture porduction and economy planning.