PROBLEM TO BE SOLVED: To provide a dispersion watercraft which can be rapidly turned and secure a running stability even when a residual quantity in a tank decreases as a dispersion object substance is dispersed.SOLUTION: In a dispersion watercraft 1 that disperses a dispersion object substance such as fertilizer or herbicide, a first hull 2 equipped with a propeller 22 and an aerial rudder 23 first hull 2 on a cockpit 20 and a second hull 2 equipped with a storage part 31 that stores the dispersion object substance are provided independently to couple the first hull 2 and the second hull 3 with a coupler 4 so as to make an angle between them. In the case of rightward turning, a rod-like coupling member 41 provided on the right side of the coupler 4 is shortened to lengthen a rod-like coupling member 41 provided on the left side of the coupler 4. Reversely, in the case of leftward turning, the rod-like coupling member 41 provided on the right side of the coupler 4 is lengthened to shorten the rod-like coupling member 41 provided on the left side of the coupler 4.