A rotating electric machine control device for controlling a rotating electric machine having a winding set with windings for multiple phases includes: an inverter having upper and lower arm elements connected to high and low potential sides, respectively, and converting an electric power of the rotating electric machine; a terminal voltage detection device detecting a terminal voltage of each phase; a resistor connecting each phase and a positive side of a power supply; and a control device having a signal generation device generating a control signal for the upper and lower arm elements and a failure detection device detecting a failure based on a sum of the terminal voltage in all phases when all control signals represents an off command, and a rotation speed of the rotating electric machine is lower than a threshold.