With a turbine of the present invention, a preferably helical partition is formed upright on the outer periphery of a rotor carried rotatably in a casing. A large number of blades are mounted between turns of the partition at a predetermined interval on the outer periphery of the rotor, and a channel for the working fluid is formed in the space between the blades and the partition on the outer periphery of the rotor. Therefore, the turbine of the present invention is capable of utilizing even a low pressure low speed low flow rate working fluid realizing a low speed rotation.