Since regional climate change has noticeably impacted on the Inner Mongolia grassland,drought has become the primary natural disaster threatening to Inner Mongolia grassland ecosystem. Based on the theory of Natural Disaster Risk,a risk assessment model about drought disaster has been developed. Using meteorological,soil moisture,vegetation,remote sensing,socioeconomic and GIS data in 54 animal husbandry counties,8 key indicators fot risk assessment were selected from four sub-systems,including hazard of the disaster-causing factors, sensitivity of disaster-formative environments, vulnerability of disaster-bearing body and capabilities of prevention and mitigation from disaster. The weights of these risk assessment indicators were determined by analytic hierarchy process,weighted comprehensive evaluation and expert scoring method. The drought disaster risk level of grassland in Inner Mongolia was then evaluated by this model. The results show that the spatial distribution of the comprehensive drought disaster risk index presents the obvious zonal distribution with higher in the south compared with the north and higher in the east compared with the west. The area of low,medium,and high level of drought disaster risk accounts for 21.3%,37.4% and 41.3% of Inner Mongolia grassland respectively. High risk areas are mainly distributed in southern of Ordos city,central southern of Baotou city,northern of Hohhot city,central Wulanchabu city,southern of XilinGol League,central of Chifeng city,most areas of Tongliao city,southwest of Xingan league and central western of Hulunbeier city. Low risk areas are mainly distributed in eastern of Bayannaoer City,central eastern of Ordos City,western Wulanchabu city,northwestward of XilinGol League,eastern of Tongliao city and western of Hulunbeier city. The model could reflect the situation of drought disaster risk over Inner Mongolia grassland and provide a reference for disaster risk management,responding to climate change, drought resistance and disaster mitigation action.