Local governments usually designed disaster response plan by themselves in order to overcome disasters. In previous research, we developed the effective analysis method for disaster response which is "BFD (Business Flow Diagram)". In this research, in order to improve effect of BFD analysis, we designed and developed WBS Manager focusing on the process of WBS development which is a part of BFD analysis, because WBS development is fundamental process of BFD method. Especially we developed WBS Manager as web-based application, and implemented it to actual studies at local governments in planning their disaster response operations. In this paper, we introduced the overview of WBS Manager.