A Method is provided for estimating a temperature of an exhaust gas in an exhaust line of an internal combustion engine. The exhaust line is provided with a NOx sensor that includes, but is not limited to a heater. The method includes, but is not limited to determining a value of a parameter indicative of a heat released by the heater of the NOx sensor, and of calculating a value of the temperature of the exhaust gas as a function of the determined value of this parameter.