Abstract: In order to correctly identify the complicated lithology of clasolite in Carboniferous reservoir in the Tahe Oilfield,the identification method was studied on the basis of conventional logging data.According to coring data,the lithology of the reservoir was divided into four types:sandstone,shaly sand,pebbly sandstone and calcareous sandstone.Extensive pertinent information regarding the lithology was taken from conventional logging data before processing in a normalization of data phase.The information of some known lithologies of coring samples was studied with conventional SVM and LSSVM,an identification method of lithology that suitable for characterizing carboniferous clasolite of the Tahe Oilfield has been obtained.In X block,the accuracy of the identification of the lithology with LSSVM was 10 Percentage point higher than that of conventional SVM.The result of the lithology identification showed that LSSVM was effective for identifying the complicated Carboniferous clasolite in the Tahe Oilfield reservoir.