In this paper blood supply chain planning in disaster situation is discussed. A new model for simultaneous midterm and short term planning is proposed in order to minimize the whole network's costs. Blood demand is considered as a stochastic phenomenon and a scenario based method is used to model this uncertainty. This model determines location of fixed blood centers which should be established after disaster (instead of centers that are ruined during the disaster)and location of mobile blood facilities (which can move in order to collect blood in each time period). Assignment of blood donors to fixed centers and mobile facilities and transportation plan for transferring blood from mobile facilities to fixed centers is also considered. The proposed model is solved using GAMS software for a case study.