The aircraft skin temperature is a basic factor determining the infrared image of aircraft, so the knowledge on the transient temperature is important. By analyzing the heat transfer mechanism governing the skin temperature, the physical and mathematical models for the transient coupled heat transfer were put forward, in which the effects of internal heat transfer in an aircraft cabin and the aerodynamic convection and radiative heat transfer outside the skin were included. A wall heat flux function was introduced to separate the numerical prediction of internal heat transfer in aircraft from that of thermal effects outside the skin. The thermal network method combined with the Monte Carlo method was used to analyze the internal heat transfer and the FLUENT code was employed to simulate the aerodynamic convection outside skin. By numerical simulation, the transient temperature fields of an aircraft skin under various flight statuses were obtained and discussed.