Abstract: On inter-city railways, the distances between stations are normally short, so that tread trimmers often operate during daily running of EMUs(Electric Multiple Units). To predict the wear of inter-city EMU wheels, a wear model integrating models of vehicle system dynamics, tread trimmer-wheel contact and wheel wear is developed, in which the wheel wear is calculated using Archard wear model, and the wear contribution of the tread trimmer−wheel interaction is distinguished from that of wheel−rail interaction. Simulating an EMU running on an inter-city line in south China, the evolution of LM wheel profile is predicted for a re-profiling period of wheels, based on which the wear coefficient related to trimmer−wheel contact is determined to be 1.45×10⁻⁴ and the model is validated through comparing to the results of monitoring tests. Prediction results have shown that the prediction error of wheel wear is just 5.00%. Taking a type of hard trimmer operating with an air pressure of 0.30 MPa as an example, an optimal working mode of the trimmer is figured out, i.e., the intermittent operation of “working 20 s – stopping 25 s”. Such a wheel wear model provides an effective tool for the optimization of the trimmer system equipped on EMUs.