Driving power output control for personal watercraft

A jet-propulsion personal watercraft comprises a body including a hull and a deck, an engine mounted in the body, a driving power output changing system configured to be able to change a driving power output of the engine, a controller configured to control an operation of the driving power output changing system, and a pressure sensor configured to be able to detect a pressure which is applied to the body from the water on which the body is floating, the pressure having a component in a lateral direction of the body, wherein the controller includes a turning determiner configured to determine whether or not the body is turning, based on a signal received from the pressure sensor; and a driving power output control unit configured to control the driving power output changing system based on information received from the turning determiner.