To provide a turbine that satisfies demands for a small size, higher performance and higher efficiency even in a field of engines and power machines using water, air, gas, steam or the like as a working fluid, to achieve further social development.

A swirling flow turbine is provided, comprising: a suction pipe having a swirl vane inside at a twisting angle of 45° as a reference; and a rotary nozzle having a nozzle flow passage which includes a meridian curve represented by θ=log{r/(ν×R)}-(R-ν×R), a curve (circle) represented by r=R and a curve connecting both curves near the perimeter of the circle r=R. As the rotating flow passage is tubular, the turbine has less frictional loss of a working fluid compared to an impeller type turbine, has a simple structure and is particularly advantageous for reduction in size, microminiaturization, higher efficiency, or the like. The turbine can contribute to the development of new technology using natural energy, various types of exhaust pressure, waste heat and the like in a field of turbine engines, high-speed rotation machines, or the like.