Although there is a drought together with an earthquake and a flood in disasters, recently, it has been hard to carry out the risk mitigation measures with the infrastructure facilities in Japan. On the other hand, there is still room for adjustment, because the drought risk has the difference between regions and between agents according to the geographical conditions and the historical background. In this study, we examined the allocation of drought risk considering not only efficiency but also equity, focusing on the saving water and water transfer between regions as the measures that do not depend on the infrastructure facilities. We show that the allocation of drought risk was well in a certain price of water transfer by comparison with the various cases using the social benefit and the differential income between regions respectively as indexes of efficiency and equity in simulation