To improve a restart failure during fuel vapor occurrence, in a fuel injection control apparatus for an engine that is not equipped with a battery and starts the engine by a manual operation, the fuel injection control apparatus for an engine includes: an injector that supplies fuel to the engine based on pressure of the fuel supplied by a fuel pump; a power generating section for generating power based on rotation driving of a crank shaft of the engine; a starting device for manually starting the engine; and a control section for starting with power generation voltage by the power generating section and calculating a fuel injection amount based on an operation state of the engine. The control section includes: an injection amount calculating function unit that calculates, according to the operation state of the engine, an injection amount of the fuel to be supplied to the engine; an injection time conversion coefficient calculating function unit that calculates an injection time conversion coefficient for converting the injection amount into injector driving time based on a predicted fuel pressure value; and an injector driving time calculating function unit that calculates driving time of the injector based on an output of the injection amount calculating function unit and an output of the injection time conversion coefficient calculating function unit.