Abstract: The frequent and serious agricultural drought often cause social and economic losses, ecological environment destruction, people psychological panic and social order imbalance, and many other social problems, if these problems didn't be given enough attention and control, it will be easy to accumulate and evolve into social risk. Define the meaning of agricultural drought society risk, identify agricultural drought society risk and classified, on this basis, the logic causes and evolution law of agricultural drought inducing social risk are explored. The evolution and path of society risk of major agricultural drought is further revealed, and then, by using the improved BASS model, the typical case of social risk caused by major agriculture drought in dingxi of gansu is empirically analyzed, at last, it puts forward some countermeasures in order to better prevent the social risk evolution of agricultural drought and to cope with the potential social crisis to provide the governance basis.