Abstract: In order to make up for the lack of theoretical research on the rail wear characteristics of No.42 high-speed turnout, a numerical prediction model for rail wear development of high-speed turnout was established. The rail wear depth distribution was calculated according to the Archard’s material wear theory and vehicle-turnout coupling dynamics simulation analysis. An adaptive-step algorithm was adopted to update the rail profiles at every characteristic section position, which could reduce the cumulative errors and improve the stability of the numerical model. The wear distribution and development rules of switch and stock rails of No.42 high-speed turnout were investigated using the theoretical prediction model. The main conclusions of the research were as follows. (1) When the train passes the turnout in the main direction, the wheel load transition proceeds from 35.0 mm section to 50.0 mm section. The wear development accelerates slowly before wheel load transition, accelerates rapidly in the wheel load transition area, and slows down after wheel load transition. (2) When the train passes the turnout in the branch direction, the train starts to run against the curved switch rail soon after it enters the turnout and the side wear of the switch rail begins to appear from the 9.1 mm section. With the gradual widening of the curved switch rail, it always has severe wear on the shoulder. The wear of straight stock rail is much smaller than that of curved switch rail although it is mainly bearing the wheel load. After the wheel load transition starts, the wear distribution of the curved switch rail becomes wider and the wear on the shoulder decreases significantly. After the full section, the wear of curved switch rail decreases significantly again. The wear of the curved stock rail is always distributed in the middle of the rail head, the wear development accelerates gradually before wheel load transition and slows down after the transition starts.