Abstract: Induction normalizing treatment after rail flash-butt welding is of critical importance to improve the service life of joints and enhance train safety. To optimize the induction normalizing process, an electro-magneto-thermal bidirectional coupling model for induction normalizing of rail flash-butt welded joints was established, and the differences between single- and dual-frequency induction normalizing were investigated by means of numerical simulation. A comparative analysis was conducted from the perspectives of the dynamic heating process of key nodes and the difference in temperature distribution uniformity in the transverse and longitudinal sections of the joint. The results show that under the same average coil heating power, the heating efficiency of dual-frequency heating increases by 14%; the rail foot easily reaches thermal equilibrium, and the temperature uniformity in the rail base region is the worst; dual-frequency heating can significantly improve temperature uniformity, and the maximum temperature difference on the end face is reduced by 21 ℃ compared with single-frequency heating; under the condition of fully covering the post-weld heat-affected zone, dual-frequency heating reduces the width of the heat-affected zone by 6 mm, which effectively reduces the width of the softened zone of the joint after heat treatment and improves the joint performance. Finally, the difference between the experimentally measured and simulated values of the node heating curves was compared, which proves the accuracy and reliability of the established model and provides guidance for the subsequent optimization of induction heating parameters.