As an important method of information fusion technology, the theory of Dempster Shafer (D S) evidential reasoning has been applied to many areas such as automation,image analysis and object identification and so on.In this paper,the method of D S evidential reasoning is introduced into wear particles identification based on statistic selection and analysis of characteristic parameters of debris,and the statistic tolerance and decision making probability of image parameters of wear particles are also given based on identification test.The program of auto identification of wear particles has been made by means of Dempster Shafer evidential reasoning,and a classifying experiment of wear particles by this method has been done.It is shown in the experiment that the identification accuracy of debris by D S evidential reasoning is very good,and the speed of classification is very fast.