PURPOSE: To prevent the push-in of the bow at the time of reversion by inclining the rear edge of a ladder for changing the jetting direction water for steering, and rotatably supporting a deflector under the ladder.

CONSTITUTION: A water jet propulsive ship is provided with an impeller 3 rotated by an engine in a water drum 1 having a sucking hole 2 opened on the bottom side, a flow straightening drum 4 is connected to the rear side of the impeller 3 of the water drum 1, and a ladder 6 is laterally rotatably connected to the rear end of the flow straightening drum 4 by upper and lower support shafts 5. The rear edge of the ladder 6 is formed into an inclined surface 7 with the upper side backward, the lower end hinge part 10 of a deflector 9 is rotatably hinged to a pump cover 8 under the ladder, and a reverse cable 1 for pulling up is connected to the deflector 9. A reverse gate 12 is provided forward on the lower surface of the ladder, 6 and a water through hole 13 is provided in the pump cover 8 according to the reverse gate 12.