An engine control apparatus includes first and second fuel injection amount calculators, a fuel injection controller, an EGR valve controller, and an EGR valve diagnosis unit. The first and second fuel injection amount calculators are configured to calculate first and second fuel injection amounts on the basis of a detected intake air amount and detected pressure in an intake pipe, respectively. The fuel injection controller is configured to control a fuel injection apparatus for an engine on the basis of a correction fuel injection amount that is a result of addition of the first and second fuel injection amounts respectively multiplied by first and second weight coefficients. When the fuel injection is restarted after diagnosis of the EGR valve carried out by the EGR valve diagnosis unit, the fuel injection controller increases the second weight coefficient, and thereafter gradually increases and reduces the first and second weight coefficients, respectively.