Provided are: a CO 2 recovery apparatus such that the total operational efficiency and stability of the apparatus can be improved even when the amount of a gas to be treated varies; and a CO 2 recovery process. This CO 2 recovery apparatus (1) is provided with: a CO 2 absorption tower (14) for bringing exhaust gas (11A) into contact with a CO 2 absorbing liquid (13) and thus making the CO 2 absorbing liquid (13) absorb the CO 2 contained in the exhaust gas (11A); a CO 2 absorbing liquid regeneration tower (15) for heating the CO 2 absorbing liquid (13) with steam and thus releasing CO 2 from the CO 2 absorbing liquid (13) and regenerating the CO 2 absorbing liquid (13); a flowmeter (101) for determining the flow rates of the exhaust gas (11A) introduced into the CO 2 absorption tower (14); and a control unit (102) for classifying the flow rates of the exhaust gas (11A) determined by the flowmeter (101) into multiple flow rate ranges, and controlling the flow rate of the CO 2 absorbing liquid (13) supplied to the CO 2 absorption tower (14) and the flow rate of steam supplied to the CO 2 absorbing liquid regeneration tower (15) on the basis of prescribed set load values which have been previously established in accordance with the multiple flow rate ranges.
