A method for estimating the junction temperature of the power semiconductor device of the power module is provided. The method includes computing a junction temperature prediction value of the first power semiconductor device based on a power loss and a thermal resistance of the first power semiconductor device and computing a junction temperature prediction value of the second power semiconductor device based on a power loss and a thermal resistance of the second power semiconductor device. A temperature prediction value of the heat sink is computed by subtracting the junction temperature prediction value of the first power semiconductor device from a sensing temperature sensed by the temperature sensor. The junction temperature of the second power semiconductor device is then finally determined by adding the temperature prediction value of the heat sink to the junction temperature prediction value of the second power semiconductor device.