Abstract: A method for controlling an engine includes the steps of sampling instantaneous flow rates of intake air supplied to the engine, computing the quantity of intake air to be supplied to the engine in an intake stroke on the basis of the sampled instantaneous intake air flow rates, computing the quantity of injected fuel in the intake stroke on the basis of the computed intake air quantity, and injecting the computed quantity of fuel to the engine. In the method, the step of computing the injected fuel quantity includes the step of computing the ratio between the instantaneous intake air flow rate sampled at a reference timing in the preceding intake stroke and that sampled at reference timing in the present intake stroke for correcting the quantity of intake air supplied in the present intake stroke.