Abstract: A system for controlling an electromagnetic clutch of an internal combustion engine mounted on a vehicle, in accordance with the engine speed and vehicle speed. The electro-magnetic clutch has a drive member secured to a crankshaft of the internal combustion engine, a magnetizing coil provided in the drive member, and a driven member adjacent said drive member. A shift lever switch produces a signal during the operation of a shift lever for the transmission. A speed sensor detects the speed of said vehicle producing a signal when the speed exceeds a predetermined value, and a clutch hold switch produces a signal when the speed of the engine exceeds a predetermined value. Both signals are fed to a control circuit. The control circuit maintains current through the magnetizing coil when the speed sensor and the clutch hold switch produce respective output signals.