Abstract: Based on the data of disaster caused by drought in 16 counties of Southeast Guizhou Province from1981～2012，Qiandongnan prefecture was divided into three regions in this paper with method of rotated principal component．The monitoring text drought data from 1981 ～ 2012 provided by the national climate center was converted to digital data．Based on SPIW₆₀、MI₃₀、SPI₉₀and SPI₁₅₀data from 1981 ～ 2010，the coefficients of the new compound drought index equation were defined with method of factors fitting technology．After inspection by monitoring drought data from 2011 ～2012，the results show that the coefficients are applicable to the area of Qiandongnan．