When the passenger compartment caught fire in the long high-speed railway tunnel, the window glasses may be deformed and break off to form new vents, which can accelerate the fire combustion. The flame will eject to tunnel from the opening and lead to catastrophic loss of casualties and properties. This paper studied the behavior characteristics of the ejected flame and the longitudinal distribution law of smoke temperature in the high-speed train compartment. Based on the energy balance equation, methods for calculating the heat release rate (HRR) in and out of the on-fire train were put forward, and the coupling relationship between the flame tilted angle and HRR was established. Moreover, the coupling relationship between the maximum dimensionless temperature near the tunnel wall and the dimensionless flame ejecting HRR was obtained. The results show that the HRR in and out of the on-fire train compartment increases in the parabolic rule. The HRR in and out of the on-fire train compartment are equal when the whole HRR is 17.85MW; the HRR in the on-fire train compartment is larger than that flame ejecting HRR when the total HRR is within the range of 1MW to 15MW. But HRR in the on-fire train compartment is smaller than that out of the on-fire train compartment when the total HRR is within the range of 20MW to 30MW. With the increase of the total HRR and hot-gas, the temperature near the tunnel wall increased, and the highest temperature appears in position of 3 meters high. The flame will eject when the HRR is above 20MW.