Abstract: In order to solve the degradation mechanism of cutting wear of roadheader,the Gamma process is cited,and Bayesian parameter updating method is used to predict the residual life of cutter based on the relationship between wear quantity and time.On the basis of monitoring data,the priori values of Gamma process parameters are determined,and then the reliability function is obtained by updating the parameters by using Bayesian method on the basis of known parameter data.Thus,the residual life of gear cutting wear can be predicted.Finally,an example is given to verify the method.The results show that under the condition of certain failure threshold,the Bayesian parameter fusion is more effective.With the increasing of cumulative accuracy of monitoring data,the predicted residual life of the new Gamma process is closer to the real value,which meets the engineering requirements and provides a reliable reference for residual life prediction of gear cutting wear.