Abstract: Drought is a primary determinant agro-meteorological disaster which constrains the potato yield in Inner Mongolia. The classification of drought risk is particularly significant for disaster risk assessment and mitigation. Utilizing meteorological data of 73 stations from 1979 to 2013, historical drought disaster records with potato yield data and social attribute data, the extent of the potato drought disaster in Inner Mongolia is investigated.Results from the use of GIS spatial analysis and the fuzzy clustering method are pertained from the aspects of drought-causing factor risk indices, the vulnerability of disaster-bearing bodies, the exposure of the disaster environment and the evaluation index system of disaster prevention and mitigation capacity in the region.Based on the regression model, thresholds for light drought, medium drought and heavy drought are derived from the regression model portrayed as linear between the percentage of negative anomalies of precipitation and the relative meteorological yield in the central western and eastern Inner Mongolia, combined with the agricultural drought grade and the precipitation anomaly percentage under the national criterion of meteorological and drought grade.It opens up opportunities to fully exploit the use of drought index as an indicator of the distribution of the drought risk, and thus it is of immense importance in monitoring the smooth decreasing tendency from west to east.High risk areas covering 19.1% are mainly distributed in northeastern Ordos, southern and northern Hohhot, most regions in Wulanchabu and Xilinhhot in the southern region. The middle risk zone is primarily distributed in some areas of Hohhot, the central and southern of Chifeng, the northwest of Tongliao, the northeast of Xing'an League, the northern of Hulunbeier, coveringing 20.1% of the total area. The lower risk areas cover 41% of the total area including the western and northern of Chifeng, the southeast of Tongliao, the southwest of Xing'an League, the southeastern of Hulunbeier, and so on.