PURPOSE: To keep a starting point of falling and scattering of a fluid at a farther distance as much as possible from an exit 3 of a nozzle of jetting the fluid in a nearly uniform speed distribution, to improve the appearance of fountain by making the water jetting posture better and to perform discharge of long distance by increasing the flying distance in the discharge nozzle.

CONSTITUTION: A flow straighting member 4 provided with a separation guide part 6 and a through-hole 7 to face each other is arranged in the vicinity of the exit 3 of the jetting nozzle 1, and a peripherally low speed distribution region S of the fluid W jetting from the jetting nozzle 1 is separated from a centrally equal speed and high speed distribution region F with the separation guide part 6 of the flow straighting member 4 and it is converted to the outside flow in the radial direction as shown by the arrow A group and only the fluid W of the centrally equal speed and high speed distribution region F is passed through the through-hole 7 as shown by the arrow B group and is jetted.