PURPOSE:To improve mixing performance and circulating performance of a stirring device by separating an odd number of draft tube into 2n+1 passages in the radial direction with a revolving cylinder corresponding to the draft tube, and connecting the top and foot ends of the passages successively. CONSTITUTION:When a revolving shaft 5 is revolved in the direction of an arrow mark 101, the fluid in the passage 23 is pushed upward by a screw blade 13 and flows into an adjacent passage 22 from its top. On one hand, the fluid in the passage 22 is pushed downward by a ribbon blade 12, and flows into the passage 21 after passing through the inside of a passage connecting plate 24. Thereafter, the fluid in the passage 21 is pushed upward by the ribbon blade 11 and flows into the top of a passage 20 after passing through the inside of a passage connecting cover 25. Further, the fluid in the passage 20 is pushed downward by a ribbon blade 10 to the foot and flows into the passage 23 after passing through the outside of a passage connecting plate 24. The fluid in the vessel is circulated along regulated passages as described above.