A water-jet propulsion personal watercraft comprises a body including a hull and a deck covering the deck from above, a water jet pump disposed on a rear portion of the body and configured to propel the watercraft, an engine mounted forward relative to the water jet pump within the body and configured to drive the water jet pump, a propeller shaft configured to connect the engine to the water jet pump, a coupling mechanism disposed behind the engine and configured to connect an output shaft of the engine to the propeller shaft, and an air cleaner box disposed behind the engine and above the coupling mechanism within the body and configured to take in air for the engine from outside.