PURPOSE: To enhance the rate of fuel consumption and properties of the exhaust gas, by a method wherein a major part of a required injection amount of fuel is injected by a single injection per cycle starting from a position in proximity to an overlap of intake and exhaust valves.

CONSTITUTION: At the time of an crank angle of 0° which is the middle of the overlapping period of the intake and exhaust valves wherein a final part of the exhaust period EX of a left-side cylinder 2 is overlapped with an initial part of the intake period IN, the fuel is injected from a left-side fuel injection nozzle 3 by a control signal emitted from a controlling unit 8 in response to a detection signal fed from a left-side pick-up coil 7, and the entire or major part of the required injection amount of the fuel is supplied in the intake period IN for the left-side cylinder 2. Next, in a right-side cylinder 2, the fuel is similarly injected at a phase delay of about 280 relative to the injection in the left-side cylinder 2. Accordingly, even when the intake gas is compressed by a compressor for a supercharger and is directly exhausted in the overlapping period of the intake and exhaust valves, discharge of unburned fuel is reduced, enabling to contrive to enhance the properties of the exhaust gas.