Abstract: Disclosed is a method for controlling fuel injection for an engine, in which, on the basis of a phenomenon that a part of fuel vaporized from a liquid film adhering to a wall surface of a fuel intake manifold remains in the intake manifold in the form of vapor fuel, the quantity of liquid film and the quantity of vapor fuel are estimated by using control parameters such as air mass flowing through a throttle valve, throttle opening, engine speed, air fuel ratio, etc.; the quantity of liquid film and the quantity of vapor fuel at a desired point of time are predicted on the basis of the result of estimation; and the quantity of fuel injection is controlled so as to make the air fuel ratio be a desired air fuel ratio. Further, the quantity of liquid film is estimated in the case where the data as to the air fuel ratio obtained by an O.sub.