A water jet propulsion watercraft includes a pair of jet propulsion devices arranged right and left of a hull centerline. Each jet propulsion device includes a jetting unit arranged to jet water, a deflector supported on the hull and arranged to rotate to right and left, the deflector including a forward drive jet port and a reverse drive jet port. Each jet propulsion device includes a bucket arranged to change between a forward drive position and a reverse drive position. The bucket includes a reflecting surface arranged to reflect the water jetted from the forward drive jet port when the bucket is at the reverse drive position, and an auxiliary nozzle including an entrance opened to the reflecting surface and arranged to jet water introduced into the entrance along a hull right/left direction. The entrance of the auxiliary nozzle is spaced away from the forward drive jet port in the hull right/left direction and does not oppose the forward drive jet port in a state where the bucket is arranged at the reverse drive position and the deflector is arranged at the straight drive position.