Provided is a dust collection method using a dust collection device. The dust collection method includes: a step of forming a rotating airflow by means of suction with a suction device, the rotating airflow progressing while spiraling along an inner wall surface of a main body; a step of supplying liquid from a supply nozzle; a step of spreading out the liquid with the rotating airflow on the inner wall surface thereby to continuously form a liquid catcher, the liquid catcher rotating as a film of the liquid; and a step of separating smoke and/or dust to outside by centrifugal force due to the rotating airflow and capturing the smoke and/or dust with the liquid catcher, the smoke and/or dust being contained in air introduced to the inside of the main body.