Abstract: Wear and rolling contact fatigue (RCF) damages directly affect the maintenance cost and service safety of railway wheel. Working in the open environment, the wheel material would face the extreme low temperature. In order to study the wear and damage evolution behaviours of wheel material at low temperature, twin-disc rolling-sliding tests were conducted at −40 ℃ for different cycles. In the present study, the ER7 wheel was selected to run against the U71Mn rail. Two series of tests were conducted. Firstly, tests were performed at the room temperature (around 20 ℃) and −40 ℃ for 60 000 cycles, and the wear and damage behaviours of wheel material were analyzed by optimal microscope and scanning electron microscope. Then, tests were performed at −40 ℃ for 5 000, 25 000, 60 000 and 150 000 cycles, respectively. The wear behaviour and the initiation and propagation of RCF cracks on wheel rollers after different cycles at −40 ℃ were analyzed in detail. The results indicated that the decrease in the temperature had influence on the wear and damage mechanism of wheel material. Compared with the room temperature, the wear rate of wheel material decreased at −40 ℃, while the surface hardness after testing increased. At the room temperature, the peeling on the wheel surface was severe, and the wear mechanism was fatigue wear. At −40 ℃, the fatigue damage on the wheel surface was alleviated. Furthermore, the wear and damage of wheel materials showed an obvious evolution characteristic. During the early wear stage (after 5 000 cycles), the wheel material transferred to the rail surface and the wear rate of wheel roller was relatively low. With the increase in the number of cycles, the wear rates of wheel rollers increased gradually and kept stable after 60 000 cycles. Concerning the surface damages, after 5 000 cycles, the worn wheel surface was dominated by spalling in small size, while large area of tribo-film could be observed on the rail surface. The formation of the tribo-film provided a protective effect for wheel material and declined the wear rate of wheel rollers. With the increase in the number of cycles, the fatigue damage on the wheel surface was gradually aggravated. Concerning the cross section of wheel rollers, after 5 000 cycles, the length of cracks on the wheel material was short. Those cracks usually propagated to the surface and formed small spalling. When the number of cycles was larger than 25 000, a large number of subsurface cracks could be observed, and those subsurface cracks would converge with adjacent cracks and accelerate the crack propagation. Therefore, long cracks with a maximum length of 709.5 μm could be observed. These cracks propagated with small angle and were nearly parallel to the rolling direction. With the increase in the number of cycles, the crack length tended to decrease as a result of the high wear rate. The wear and damage behaviours of wheel steel at −40 ℃ was obviously different from those at the room temperature. Compared with the room temperature, the wear of wheel was decreased at −40 ℃, but the damage on the subsurface of wheel was severer. In the early wear stage (after 5 000 cycles), material transfer occurred at the wheel-rail interface and a tribo-film was formed on the rail surface. The tribo-film could reduce the wear of wheel steel, which would lead to the continuous accumulation of plastic deformation on wheel rollers. In the later wear stage, the highly deformed wheel surface material promoted the crack initiation. Therefore, a large number of cracks could be observed in the subsurface on wheel rollers. These subsurface cracks would meet each other and accelerate the crack propagation.