An air pollution control system comprises a SOx removal equipment for reducing sulfur oxides from flue gas from a boiler, a cooler for reducing the sulfur oxides that remain in the flue gas and for decreasing a gas temperature, CO2 recovery equipment including an absorber for bringing CO2 in the flue gas into contact with a CO2 absorption liquid so as to be reduced, a regenerator for causing the CO2 absorption liquid to emit CO2 so as to recover CO2 and regenerate the CO2 absorption liquid, a heat exchanger which for decreasing a temperature of the flue gas, and calcium carbonate spraying equipment for spraying calcium carbonate between the heat exchanger and an electric dust collector, wherein a mist generation material in the flue gas is converted from a gas state to a mist state to arrest and reduce the mist generation material in the mist state using calcium carbonate.