To provide a rotary apparatus capable of establishing a high efficiency, stable operation, and a long service life with simple configuration.

This rotary machine is either a crossing spiral compressor or a pump having a cylindrical rotor rotating inside a cylindrical stator hole. The outer surfaces of the rotor and hole include a plurality of spiral fluid flowing grooves separated by thin blades, wherein the spiral fluid flowing grooves in the stator hole draw a spiral in the opposite direction to the spiral fluid flowing grooves in the stator. Each fluid flowing groove in the rotor and hole has an opening facing an annular gap between the rotor and stator, and grooves intersect in many places in order to facilitate replacement of the fluid between the rotor grooves and hole grooves.