CONTROLLER FOR INTERNAL COMBUSTION ENGINE

A controller is configured to control an internal combustion engine. The controller is configured to perform a fuel pressure control of adjusting a fuel pressure downstream of an electromagnetic valve in a flow direction of fuel in a fuel passage to a prescribed pressure lower than a fuel pressure upstream of the electromagnetic valve by repeatedly performing opening and closing operations of the electromagnetic valve. The controller includes processing circuitry. The processing circuitry is configured to execute a process of setting opening and closing time points of the electromagnetic valve such that a valve opening period of the electromagnetic valve during execution of the fuel pressure control overlaps with a valve opening period of the fuel injection valve.