PURPOSE: To provide a water intake device for propelling a water jet propulsion boat with a hydrofoil, which controls the flow of water flowing toward a water intake, for preventing the increase of a resistance of the water intake in sailing.

CONSTITUTION: At immediately before of a propulsion water intake 5, front edges of a pair of current plates 8, 8 are pivotally attached to a supporting shaft 7, and these current plates 8, 8 can be opened by insertion of a wedge 10a, thereby, the degree of opening can be adjusted. In a water jet proplusion boat with a hydrofoil, since the suction amount of seawater into the water intake 5 is decreased according to the decrease of required thrust just after a hull is floated up to the water surface by lift of the hydrofoil, the current plates 8, 8 are opened to direct the flow of water flowing toward the water intake 5, and to decrease the amount of stagnation, thereby, the resistance of the water intake 5 can be decreased in sailing with the hydrofoil.