PURPOSE: In a high speed water flow jet pump, to enable feed of mixture of gas and liquid where solid material can be fed easily, by placing a conduction tube having a nozzle and a cavitation drop regulating port between a pressure feed pipe and delivery pipe.

CONSTITUTION: High speed water flow fed through a nozzle 3 from a pressure feed pipe 1 will suck gas or liquid from a cavitation drop regulating port 4 on the outercircumference at the tip of the nozzle 3 to prevent cavitation and jet into a delivery pipe 6 without lowering the efficiency. Consequently the static water in the delivery pipe 6 is induction accelerated to enable suction/feed of even solid material, particles, vinyl, rope, etc. through the tip of the suction pipe 5. Since the cavitation drop can be regulated simply by means of the cavitation drop regulating port 4 made in the outercircumference of the conduction pipe 2, it can be operated easily.