Abstract: Geological hazard assessment is important content to study harmony of human being and earth, which can afford the basic gist for prophase work of the large-scale engineering build. Two basic factors such as harmfulness of historical, harmfulness of latent disaster and eight relevant estimate factors is selected.Fuzzy synthetical evaluation method is adopted to evaluate the danger level geological hazard in the hydropower station construction of LianLu,GanSu Province. Result indicate:geological hazard level in river and the mountai basin arear is middle, geological hazard level is weak in medium mountain arear.