The invention discloses an open-air dust-removal system, which comprises a high rod atomizing device, a charging demisting dust-removal device, a dust concentration sensor, an air humidity sensor, an anemometer, a controller and an automatic retractable dust collecting plate, wherein signals acquired by the dust concentration sensor, the air humidity sensor and the anemometer are transmitted to the controller; the controller calculates the atmospheric dust concentration, the air humidity and the outside wind speed at the moment according to the received data; the controller controls the high rod atomizing device and the charging demisting dust-removal device according to the calculated atmospheric dust concentration, air humidity and outside wind speed, and controls the automatic retractable dust collecting plate to be unfolded or folded. The open-air dust-removal system can fulfill the purpose of dust removal in a safe, energy-saving, high-efficiency and self-adapting to external environment manner.