Abstract: A thermo-elastic plane strain finite element model incorporating multiple surface cracks in rail is established by using a thermo-mechanical coupling finite element method. In the numerical model, the temperature-dependent material properties are considered. The movement of wheel-rail contact forces and fictional heat resource is used to simulate the wheel sliding on the rail. The effect of multiple crack interaction and number of cracks on the crack growth behavior in rail is investigated during wheel-rail full slip contact. The results indicate that comparing to the single crack, the multiple crack interaction can reduce the possibility of crack growth. The stress intensity factor K1 and stress intensity factor range ?K2 of cracks in rail decrease with increasing the number of cracks. Only five cracks in rail can reveal the interaction among many cracks.