Abstract: Considering many geographical spatial objects and influence factors in the process of loss-of-life evaluation caused by dam breach,an evaluation method of loss-of-life caused by dam breach based on GIS and neural networks optimized by genetic algorithms is proposed.The calculation model for estimating loss-of-life caused by dam breach is established based on GIS spatial information grid model.The influence factors of loss-of-life caused by dam breach were analyzed.The evaluation index system is established by grey relation degree model.A fast evaluation system of loss-of-life caused by dam breach based on GIS is implemented.Scheme and GIS technologies for the system were analyzed.Application shows accuracies and good effects of the evaluated method.