A fuel injection system for an engine, the fuel injection system includes injectors and an electronic control unit. The injectors include needle valves; and the ECU is configured to: (i) execute partial lift injection and full lift injection with the injectors, the partial lift injection being injection during which the needle valve does not reach a fully-open state and the full lift injection being injection during which the needle valve reaches the fully-open state; (ii) operate the engine in a partial lift injection region where the injection of a required injection amount of a fuel is shared by the partial lift injection and the full lift injection; and (iii) perform the amount of correction of the required injection amount with respect to the injection amount shared by the full lift injection when the required injection amount is corrected while the engine is operated in the partial lift injection region.