PURPOSE: To conduct secure fuel cut even during travelling at a high speed by closing an electromagnetic valve for fuel shut-off at the time of predetermined deceleration, and under this condition, opening and closing an electromagnetic valve for returning fuel in response to the compression and intake of a plunger pump.

CONSTITUTION: The number of revolution of an engine is detected by a sensor 21, the load of the engine is detected by a sensor 22 and also on the basis of the respective detected signals it is judged by means 23 whether it is the time of predetermined deceleration or not. When it is judged to be the time of deceleration, a valve closing signal from means 24 is output to an electromagnetic valve 15 for fuel shut-off provided at an intake passage connected to a high pressure plunger chamber. Meantime, a plunger lift is detected by a sensor 25, and according to this detected signal it is judged by means 26 whether a plunger pump is under an intake stroke or under a compression stroke. As a result, according to the compression stroke and the intake stroke, opening/ closing signals are output from means 27 to open and close an electromagnetic valve 14 provided a fuel return passage.