In this paper, we propose a system configuration that reduces processing time to realize real-time evacuation simulation of urban flood damage and discuss feasibility of immediate processing from prototype system. The purpose of our research is to develop a system to estimate the effectivity of urban flood damage and countermeasure by using this flood prediction result. In general, in the calculation processing, the calculation amount increases as the target area becomes wider. Processing time often takes several hours to several tens of hours for calculation, therefore immediate processing on the assumption value of flooding depth and human flow against flooding has difficulty. Therefore this paper considers the possibility of real-time evacuation simulation from the viewpoint of processing performance. We develop a prototype system of simulation for flood evacuation in order to enable immediate processing. The system shows some requirements for stable operation and the feasibility of real-time evacuation simulation.