An exhaust gas purifying apparatus, comprising: an electrolyzed alkaline water generator (10, 10a-d) which includes a cathode (13a, 13b) and an anode (12a-d), and in which water to be electrolyzed is electrolyzed through application of voltage across the electrodes, to generate electrolyzed alkaline water; an exhaust gas absorption tower into which exhaust gas can be introduced; an electrolyzed alkaline water supply line through which the electrolyzed alkaline water generated in the electrolyzed alkaline water generator (10, 10a-d) can be introduced into the exhaust gas absorption tower; a spray nozzle of the electrolyzed alkaline water, provided inside the exhaust gas absorption tower, the exhaust gas purifying apparatus being configured to purify the exhaust gas by spraying the electrolyzed alkaline water through the spray nozzle such that the electrolyzed alkaline water and the exhaust gas introduced into the exhaust gas absorption tower are brought into gas-liquid contact with each other,; and a scrubber wastewater storage section that recovers the electrolyzed alkaline water sprayed from the spray nozzle, and a scrubber wastewater return line through which scrubber wastewater from inside the scrubber wastewater storage section is returned to the electrolyzed alkaline water generator (10, 10a-d), characterized in that an air diffuser device is provided in the scrubber wastewater storage section at the bottom of the exhaust gas absorption tower, wherein the air diffuser device is configured to blow air into the scrubber wastewater that is stored at the bottom of the exhaust gas absorption tower, and the electrolyzed alkaline water generator (10, 10a-d) includes the anode (12a-d) formed of Mg or a Mg alloy. an electrolyzed alkaline water generator (10, 10a-d) which includes a cathode (13a, 13b) and an anode (12a-d), and in which water to be electrolyzed is electrolyzed through application of voltage across the electrodes, to generate electrolyzed alkaline water; an exhaust gas absorption tower into which exhaust gas can be introduced; an electrolyzed alkaline water supply line through which the electrolyzed alkaline water generated in the electrolyzed alkaline water generator (10, 10a-d) can be introduced into the exhaust gas absorption tower; a spray nozzle of the electrolyzed alkaline water, provided inside the exhaust gas absorption tower, the exhaust gas purifying apparatus being configured to purify the exhaust gas by spraying the electrolyzed alkaline water through the spray nozzle such that the electrolyzed alkaline water and the exhaust gas introduced into the exhaust gas absorption tower are brought into gas-liquid contact with each other,; and a scrubber wastewater storage section that recovers the electrolyzed alkaline water sprayed from the spray nozzle, and a scrubber wastewater return line through which scrubber wastewater from inside the scrubber wastewater storage section is returned to the electrolyzed alkaline water generator (10, 10a-d), characterized in that an air diffuser device is provided in the scrubber wastewater storage section at the bottom of the exhaust gas absorption tower, wherein the air diffuser device is configured to blow air into the scrubber wastewater that is stored at the bottom of the exhaust gas absorption tower, and the electrolyzed alkaline water generator (10, 10a-d) includes the anode (12a-d) formed of Mg or a Mg alloy.