An injector control device (2; 2A) that controls driving of an injector that performs multi-stage injection in which fuel injection is divided into a plurality of injections in a single cycle of an engine, the injector control device comprising: an injection amount setting unit that sets, as a total injection amount, a total of fuel injection amounts in the multi-stage injection in the single cycle, and sets, as a preceding injection amount, a fuel injection amount in a preceding injection that is executed prior to a main injection in the multi-stage injection and that is less than a fuel injection amount in the main injection; an energization period setting unit that sets an energization period of the injector based on the total injection amount and the preceding injection amount set by the injection amount setting unit; an injector driving unit that controls driving of the injector based on the energization period set by the energization period setting unit, and a small injection amount region determination unit that determines whether the total injection amount is within a small injection amount region, characterized in that the injection amount setting unit executes control such that an engine speed of the engine is in proportion to the load on the engine, whereby if the engine speed drops the injection amount setting unit executes control for increasing the total injection amount and if the engine speed rises the injection amount setting unit executes control for reducing the total injection amount, sets the total injection amount for keeping the engine speed constant, and sets a fuel injection amount that is a predetermined percentage of the total injection amount as the preceding injection amount when the small injection amount region determination unit determines that the total injection amount is within the small injection amount region based on the total injection amount being less than or equal to a predetermined fuel injection amount, the predetermined percentage is a ratio of the preceding injection amount to the total injection amount when the preceding injection amount is less than or equal to the fuel injection amount in the main injection, and the predetermined fuel injection amount is the total injection amount when the fuel injection amount of the predetermined percentage of the total injection amount is less than or equal to a guaranteed minimum injection amount of the injector. an injection amount setting unit that sets, as a total injection amount, a total of fuel injection amounts in the multi-stage injection in the single cycle, and sets, as a preceding injection amount, a fuel injection amount in a preceding injection that is executed prior to a main injection in the multi-stage injection and that is less than a fuel injection amount in the main injection; an energization period setting unit that sets an energization period of the injector based on the total injection amount and the preceding injection amount set by the injection amount setting unit; an injector driving unit that controls driving of the injector based on the energization period set by the energization period setting unit, and a small injection amount region determination unit that determines whether the total injection amount is within a small injection amount region, characterized in that the injection amount setting unit executes control such that an engine speed of the engine is in proportion to the load on the engine, whereby if the engine speed drops the injection amount setting unit executes control for increasing the total injection amount and if the engine speed rises the injection amount setting unit executes control for reducing the total injection amount, sets the total injection amount for keeping the engine speed constant, and sets a fuel injection amount that is a predetermined percentage of the total injection amount as the preceding injection amount when the small injection amount region determination unit determines that the total injection amount is within the small injection amount region based on the total injection amount being less than or equal to a predetermined fuel injection amount, the predetermined percentage is a ratio of the preceding injection amount to the total injection amount when the preceding injection amount is less than or equal to the fuel injection amount in the main injection, and the predetermined fuel injection amount is the total injection amount when the fuel injection amount of the predetermined percentage of the total injection amount is less than or equal to a guaranteed minimum injection amount of the injector.