Abstract: A heat engine speed governor in which a differential mechanism has its input shaft operatively connected to a unidirectional electric motor, an input shaft connected to a heat engine and an output shaft connected to a fuel metering member of the heat engine. An electric motor speed control channel has a measuring means for measuring speed of the shaft connected to an input of a device for forming a control signal which has a master input connected to an output of a device for forming an electric motor speed control program. A means for measuring speed of the input shaft in a channel for correcting the electric motor speed in accordance with the heat engine speed is connected to a differentiating unit having an output connected to a correcting input of the device.