Resettlement and rehabilitation generally means the moving house not of one´s own accord and helping settle down caused by engineering projects. The decision includes layout decision and management decision and this is a new issue in China and abread. Based on GIS, the DSS for resettlement and rehabilitation is an efficient means for science decision. This paper probed into the theory and method of decision-making support for resettlement and rehabilitation, and made an experiment in line with Wanjiazhao Reservoiv Project.