PURPOSE: To promote the improvement of energy collecting efficiency, by providing a spiral windmill (water turbine), which collects energy of wind, wave, tide, river water flow, etc., and several sheets of spiral blades in the periphery of a shaft along its lengthwise direction.

CONSTITUTION: Several sheets of spiral blades 2 are mounted to the periphery of a cylindrical barrel member 4 along its axial direction, and a spiral windmill (water turbine) is constituted by inserting a shaft 1 into the center part of said barrel member 4 and connecting both the shaft 1 and the member 4 in a connection part 3. Or the spiral windmill (water turbine) is constituted by fixing the shaft 1 through the connection part 3 to both ends of a structure in which the several sheets of spiral blades 2 are integrally connected by a plurality of connecting pipe bars 6. And such constituted spiral windmill (water turbine), which is rotatably mounted by supporting both ends of said shaft 1 to a supporting bed 32 through bearings 29, is turned utilizing a flow of air and water.