A fuel injection control apparatus for an engine having a variably operated engine valve (9, 10) in which at least a closure timing of an intake valve is variably controlled, the fuel injection control apparatus detecting the closure timing of the intake valve based on a rotational phase of an intake side camshaft with respect to a crankshaft; the apparatus comprising: an intake valve closure state determining section determining that the closure timing of the intake valve is in a steady state when a control target value of the closure timing of the intake valve representing a target phase angle of the intake side camshaft is approximately constant and/or a deviation between an actual closure timing of the intake valve and the control target value thereof falls within a predetermined range, said intake valve closure state determining section otherwise determining that the closure timing of the intake valve is in a transient state; and a fuel injection quantity calculating section calculating a volume of a cylinder from the control target value of the closure timing of the intake valve when the intake valve closure state determining section determines that the closure timing of the intake valve is in the steady state and from the actual closure timing of the intake valve when the intake valve closure state determining section determines that the closure timing of the intake valve is in the transient state, calculating a volume air quantity within the cylinder on the basis of the calculated volume of the cylinder and a fresh-air rate within the cylinder, calculating a mass air quantity sucked into the cylinder on the basis of a mass air quantity within an intake manifold of the engine calculated by income and outgo calculations of inflow and outflow quantities of a mass air within the intake manifold, the volume air within the cylinder, and a volume of the intake manifold, and calculating a fuel injection quantity on the basis of the mass air quantity sucked into the cylinder. an intake valve closure state determining section determining that the closure timing of the intake valve is in a steady state when a control target value of the closure timing of the intake valve representing a target phase angle of the intake side camshaft is approximately constant and/or a deviation between an actual closure timing of the intake valve and the control target value thereof falls within a predetermined range, said intake valve closure state determining section otherwise determining that the closure timing of the intake valve is in a transient state; and a fuel injection quantity calculating section calculating a volume of a cylinder from the control target value of the closure timing of the intake valve when the intake valve closure state determining section determines that the closure timing of the intake valve is in the steady state and from the actual closure timing of the intake valve when the intake valve closure state determining section determines that the closure timing of the intake valve is in the transient state, calculating a volume air quantity within the cylinder on the basis of the calculated volume of the cylinder and a fresh-air rate within the cylinder, calculating a mass air quantity sucked into the cylinder on the basis of a mass air quantity within an intake manifold of the engine calculated by income and outgo calculations of inflow and outflow quantities of a mass air within the intake manifold, the volume air within the cylinder, and a volume of the intake manifold, and calculating a fuel injection quantity on the basis of the mass air quantity sucked into the cylinder.