A rotational flow and sink flow coupling integrated system for desulphurization and dedusting, comprising spray layers mounted in a tower body, a slurry pool arranged below the tower body, and a circulating pump mounted in the slurry pool, wherein, further comprising a rotational flow and sink flow coupling device which is mounted above the slurry pool and below the spray layers, and a tube bundle-type dedusting and demisting device arranged on the top of the tower body, wherein, the rotational flow and sink flow coupling device comprises a plurality of rotational flow and sink flow coupling units and supporting beams for supporting the rotational flow and sink flow coupling device located below the rotational flow and sink flow coupling units, adjacent rotational flow and sink flow coupling units being connected with a closing plate, each of the rotational flow and sink flow coupling units comprising a rotational flow cylinder, the rotational flow cylinder being provided with a rotational flow rotor and on the top of the rotational flow cylinder a flow guiding device is arranged, said rotational flow rotor comprising an inner cylinder body and rotational flow blades, wherein an inner diameter of the flow guiding device at a position where the flue gas flows out is less than that at a position where the flue gas flows in; and the tube bundle-type dedusting and demisting device comprises a plurality of dedusting and demisting units, each of which comprises a flow guiding cylinder and a number of n turbulent flow rotors provided inside the flow guiding cylinder, where n≤1, the turbulent flow rotors being disposed up and down perpendicularly to the wall of the flow guiding cylinder, wherein a water baffle ring is provided on the inner wall of the flow guiding cylinder of the tube bundle-type dedusting and demisting device, for forming a liquid film containing a steady amount of liquid. the rotational flow and sink flow coupling device comprises a plurality of rotational flow and sink flow coupling units and supporting beams for supporting the rotational flow and sink flow coupling device located below the rotational flow and sink flow coupling units, adjacent rotational flow and sink flow coupling units being connected with a closing plate, each of the rotational flow and sink flow coupling units comprising a rotational flow cylinder, the rotational flow cylinder being provided with a rotational flow rotor and on the top of the rotational flow cylinder a flow guiding device is arranged, said rotational flow rotor comprising an inner cylinder body and rotational flow blades, wherein an inner diameter of the flow guiding device at a position where the flue gas flows out is less than that at a position where the flue gas flows in; and the tube bundle-type dedusting and demisting device comprises a plurality of dedusting and demisting units, each of which comprises a flow guiding cylinder and a number of n turbulent flow rotors provided inside the flow guiding cylinder, where n≤1, the turbulent flow rotors being disposed up and down perpendicularly to the wall of the flow guiding cylinder, wherein a water baffle ring is provided on the inner wall of the flow guiding cylinder of the tube bundle-type dedusting and demisting device, for forming a liquid film containing a steady amount of liquid.