Recently, typhoon-induced heavy rainfalls in Taiwan always caused severe regional inundations often and often, and led to serious disasters, especially in the densely populated urban areas. It is desirable to develop an effective deployment of rescuing capacity for saving the life in the mitigating works of urban flood disasters. At present, the making-decision to deploy the rescuing capacity of flood disasters still relied on individual experience judgments of experts. This paper aimed to develop a new decision support model of deployment of rescuing capacity to mitigate flood disasters. The Tainan city was illustrated, and the methods including questionnaire survey, Analytic Hierarchy Process (AHP) and linear programming (LP) were adopted in this paper. The proposed support model can be used to integrate systematically all kinds of information and support an optimal decision in the deployment of rescuing capacity. The findings showed that the proposed model was practical and effective by the verification of two actual records of the 2012 Rend flood and the 2013 Xinhua flood, which can supply a helpful reference for firefighting department.