A water jet propulsion boat includes a fuel pump driven by an electric control unit and arranged to deliver fuel from a fuel tank to an engine via a fuel pipe, and a fuel pressure sensor arranged to detect a pressure of the fuel delivered to the engine by the fuel pump. When a magnitude of the fuel pressure detected by the fuel pressure sensor is less than a predetermined magnitude, the fuel pump is activated. On the other hand, when the magnitude of the fuel pressure detected by the fuel pressure sensor is equal to or greater than the predetermined magnitude, the fuel pump is deactivated. Also, when the fuel pressure detected by the fuel pressure sensor becomes equal to or less than an abnormal threshold value, either one or both of the fuel pump and the engine are deactivated. The water jet propulsion boat lowers power consumption, reduces battery size, extends battery life, and lowers costs.