Abstract:Affected by steep landform,complex lithology,intensive geotectonic movement,and unreasonable economic activities,about 280 geological hazards including collapses,landslides,debris flows,and potential unstable slopes are distributed in Shimian County,Sichuan Province.The occurrence of the geological hazards are closely related to rainfall.According to field investigation,debris flows usually breaks out just on the day when intraday precipitation is supreme and however,slope hazards such as collapses and landslides usually occur 2~5 days later.In this study,6 geological regions were zoned firstly based on landform and lithology.Then their occurrence and rainfall process were analyzed respectively and a certain warning line was set up according to the rainfall indexes including intraday rainfall and antecedent rainfall.Finally,meteorological warning grade was confirmed and a series of warning system including 18 warning maps were established.This research can provide a scientific guideline for the warning and mitigation of geological hazards in Shimian County.