Linzhi area of Tibet is one of the most dangerous regions threatened by debris flows in China.Under the influence of global warming,the melting rate of glacier has accelerated in this area,leading to frequent initiations of glacier-melting debris flows,which is severely hazardous.Since the middle of July,2009,the authors had carried out systematic investigations regarding approximately thirty debris flow gullies in counties of Linzhi,Milin,Bomi and Chayu in Linzhi area.Based on analysis of the twenty typical debris flow gullies and related historic documents,debris flows were divided into four classes according to initial water conditions,namely,rainfall-induced debris flow,glacier-rainfall-induced debris flow,avalanche-induced debris flow,and lake-outburst-induced debris flow.The initiation conditions were analyzed regarding landform,soil source,water source and air temperature.Specific advices based on the analysis were recommended for disaster prevention.