Recently, there has been a growing concern regarding the severity of flood inundation, and the role of disaster response has become increasingly complex. As the number of problems to be addressed has been on the rise, the limits of individual disaster response capabilities have also been suggested. Therefore, disaster-response activities, whose contents change with time, should be regarded as a series of time-connected processes, and the issues of prolonged disaster responses should be reexamined. This study focused on the relationship between the evacuation of residents at the time of flooding and the subsequent rescue activities. Based on a flooding scenario in a real urban area, simulations were used to examine how different evacuation choices of residents may affect the subsequent rescue activities in the flooded area. The results show that the behavioral models desired in conventional studies of evacuation behavior do not necessarily lead to equally good outcomes throughout the entire disaster response. As a contribution of this study, a dilemma structure was found in which choosing risky evacuation behavior in the short term can ultimately improve the rescue situation. In addition, when residents themselves select their own evacuation behavior, it was found that the evacuation awareness of each resident affects the safety of other residents in the community and that the personal safety of a person is affected by the evacuation awareness of all community residents. It was suggested that not only the response of the government but also the attitude change of individual residents is important to solve this social dilemma.