On the basis of a case study regarding the geographical conditions of Sichuan

according to materials provided by relevant units

this paper studies the landslide hazard rank division in Sichuan.Topography

stratum lithologic character

faulted structure

average annual rainfall

water system

seismic intensity are taken as landslide major effect factors.Pattern recognition is used to carry out the landslide hazard rank division.A series of control tests

such as weight of factor and selection of threshold

are conducted for danger coefficient formula.Feasibility of method is validated and uncertainty is reduced.Concept of″identifying rate″and″change rate″are proposed and RTS test is used for the method

which takes the high identifying rate and steady change rate as classifying standard.The optimal parameters are selected which can reflect the recognition results reasonably.Altogether three times recognition are taken to realize seven rank divisions in landslide hazard of Sichuan.The results from pattern recognition method coincide well with landslide occurrence.The method also can be used for other region′s landslide hazard rank division.