A required fuel amount for an engine is calculated at a predetermined calculation cycle. A fuel injection amount to be injected from an upstream injection valve and a fuel injection amount to be injected from a downstream injection valve are then calculated. After fuel injection on the basis of the calculated fuel injection amounts, a lack of fuel delivered by the fuel injection amounts immediately before re-calculation of a required fuel amount at the calculation cycle until the end of an intake stroke (end of an intake valve opening period), is calculated by subtracting the fuel injection amounts from the re-calculated required fuel amount. The calculated lack of fuel amount is injected from the downstream injection valve during the intake stroke, e.g., in stages 6 and 7. A portion of a fuel injected from each of the fuel injection valves which has adhered on an inner wall of an intake pipe and subsequently released to be later supplied to the engine, is calculated in accordance with a predetermined adhesion ratio and a predetermined release ratio. The above lack of fuel amount is determined in consideration of the calculated portion of the fuel. The lack of fuel amount is additionally injected, e.g. a fuel correction amount, even during an engine transient state, and engine operability and fuel consumption are improved.