Abstract: Geological disaster monitoring & warning engineering effectively protects the safety of people's life and property and the Yangtze shipping in the three gorges reservoir area.In order to measure its economic benefits,based on defining the boundaries of input and output of geological disaster monitoring & warning engineering in the three gorges reservoir area,this study constructs a set of detailed input and output index system.And then,according to the comprehensive analysis of the types,features,environmental conditions,and space-time characteristics of geological hazard,the evaluation models and methods of the expectation and actual possible value of economic benefits for the geological disaster monitoring & warning engineering in the three gorges reservoir area is built,and using the basic data of Zhangjiawan landslide in Guojiaba Town,Zigui Conty as an example to be analyzed and tested.This research fruits can provide decision-making method for the geological disaster monitoring,warning and control in the three gorges reservoir area.