Abstract: In a method and a device for the measurement of the mean temperature of components, a sequence of test pulses of increasing duration is applied to the component, the power of the pulses representing a state of operation of the component, a measurement of junction temperature being performed at the end of each pulse to obtain a curve representing the progress of the junction temperature of the component as a function of time on the basis of the temperature measurement points obtained at the end of each pulse. The disclosed method and device can be applied especially to determine the junction temperature of microwave electronic components working in continuous mode or in pulsed mode.