PURPOSE: To provide the stabilizer function which can easily tilt a hull in the sharp turn with the small propulsion resistance of the hull, permits the vessel width for securing the installation space for a seat for codriver, and hardly happens overturn, even if the hull is tilted in turn.

CONSTITUTION: As for the hull 1 of a hydrojet propulsion vessel, a vessel side part on the upper side from the draft line on both the sides of a stern part is projected outward, and a broad part is formed in the vessel inside the projection part 4, and a rear part seat 32 is formed in the board part, and the projection part 4 has a horizontal plane on the undersurface, and in turn, a chine is formed by the tilt of the hull 1, by the horizontal surface.