A process for monitoring the rotation of a DC electric motor, wherein the voltage and the intensity of the current supplying the motor are measured in a manner sampled over time and wherein, for each sampling instant tn, an estimate &thgr;n, of the angular position is calculated as a function of a determined or known position for a previous sampling instant and of an estimate of a value of angular speed between these two instants, which is dependent on the voltage and on the intensity of current measured for the sampling instant tn, and/or for one or more previous sampling instants.