ROTATING MACHINE

PROBLEM TO BE SOLVED: To further surely suppress a rotating stall, and to enlarge a working area.SOLUTION: This rotating machine comprises: a cylindrical casing 20; a rotating shaft 10 rotatably arranged in the casing 20; a plurality of vanes 12 which are arranged in a flow passage 29 between the rotating shaft 10 and the casing 20 in the circumferential direction around the rotating shaft 10; and a suppression part 40A which is arranged at the internal peripheral face 20a of the casing 20 or the external peripheral face of the rotating shaft 10 at the upstream side of the flow direction of a fluid in the flow passage 29 rather than front edges 12a of the vanes 12 so as to be relatively rotatable with respect to the vanes 12, and suppresses the growth of a swirl formed in the vicinity of the front edges 12a of the vanes 12.