To carry out control for preventing overheat of a coil and a permanent magnet in a rotating electrical machine.

A rotating electrical machine control system 10 comprises: a power supply circuit 12; a rotating electrical machine 14; an inverter ECU 40 which controls operation of an inverter 24 included in the power supply circuit 12; and a control unit 50 which controls as a whole operation of these components described above. A storage unit 44 connected to the control unit 50 stores a temperature difference map 46 related to temperature difference between coil temperature T_C and magnet temperature T_M, and a limit start temperature map 48 related to carrier frequency f and limit start temperature T₀. The control unit 50 comprises an output limit module 52 which limits output from the rotating electrical machine 14 on the basis of the carrier frequency f and the coil temperature T_C by using these maps.