Abstract:A group of debris flows were triggered by heavy rainfall in Wangmo County,Guizhou Province inthe early morning,June 6,2011.The debris flows were distributed mainly in upstream catchments of DajianRiver,Dayi River,and Lewang River in the north of Wangmo County.The group of debris flows was thelargest occurrence since 1949,which caused numerous losses of lives and property damages.These debrisflows were featured by low frequency,less viscosity debris flow,strongly erosion in the channels and largeintensity of rainfall.The deposition on the fans and burial of houses were the major hazardous aftermath ofthese debris flows.It is very likely that these kinds of debris flows could be triggered again under the sameheavy rainfall in the future.Preventive suggestions including evacuation and engineering projects were proposed to mitigate this kind of hazards.