A CO 2 recovery system (10A; 10B; 10C) comprising: a CO 2 absorber that: transports flue gas comprising CO 2 into contact with a CO 2 absorbent to remove CO 2 from the flue gas, and discharges a rich solution that has absorbed the CO 2; an absorbent regenerator that separates the CO 2 from the rich solution to regenerate the CO 2 absorbent as a lean solution; a gas discharge line (L 21) where a CO 2 entrained gas, discharged from a top portion of the absorbent regenerator, is discharged; a reflux water drum, disposed in the gas discharge line (L 21), that produces reflux water by separating the CO 2 and water from the CO 2 entrained gas; a separation-gas discharge line (L 22) where the CO 2 gas separated by the reflux water drum is discharged; a compressor disposed in the separation-gas discharge line (L 22) that compresses the separated CO 2 gas; a condensate water drum, disposed in the separation-gas discharge line (L 22), that produces compressor condensate water by separating the water from the compressed CO 2 gas; and a compressor-condensate water line (L 30), connected to the condensate water drum, that supplies the compressor condensate water as in-system supply water or out-of-system supply water; characterized in that: a reclaiming device that regenerates the CO 2 absorbent, wherein: the reclaiming device is connected to an end portion of the compressor-condensate water line (L 30) and includes: a branch line (L 10) that draws a part of the lean solution as lean drawn liquid, a reclaimer that takes in and reserves the lean drawn liquid, an alkaline-agent supply unit that supplies an alkaline agent into the reclaimer via an alkaline supply line (L 11), a reflux-water supply line (L 12) that supplies the reflux water into the reclaimer, a recovery-steam discharge line (L 13) that supplies recovery steam discharged from the reclaimer to a bottom portion side of the absorbent regenerator, and a heating unit that heats an inside of the reclaimer. a CO 2 absorber that: transports flue gas comprising CO 2 into contact with a CO 2 absorbent to remove CO 2 from the flue gas, and discharges a rich solution that has absorbed the CO 2; transports flue gas comprising CO 2 into contact with a CO 2 absorbent to remove CO 2 from the flue gas, and discharges a rich solution that has absorbed the CO 2; an absorbent regenerator that separates the CO 2 from the rich solution to regenerate the CO 2 absorbent as a lean solution; a gas discharge line (L 21) where a CO 2 entrained gas, discharged from a top portion of the absorbent regenerator, is discharged; a reflux water drum, disposed in the gas discharge line (L 21), that produces reflux water by separating the CO 2 and water from the CO 2 entrained gas; a separation-gas discharge line (L 22) where the CO 2 gas separated by the reflux water drum is discharged; a compressor disposed in the separation-gas discharge line (L 22) that compresses the separated CO 2 gas; a condensate water drum, disposed in the separation-gas discharge line (L 22), that produces compressor condensate water by separating the water from the compressed CO 2 gas; and a compressor-condensate water line (L 30), connected to the condensate water drum, that supplies the compressor condensate water as in-system supply water or out-of-system supply water; characterized in that: a reclaiming device that regenerates the CO 2 absorbent, wherein: the reclaiming device is connected to an end portion of the compressor-condensate water line (L 30) and includes: a branch line (L 10) that draws a part of the lean solution as lean drawn liquid, a reclaimer that takes in and reserves the lean drawn liquid, an alkaline-agent supply unit that supplies an alkaline agent into the reclaimer via an alkaline supply line (L 11), a reflux-water supply line (L 12) that supplies the reflux water into the reclaimer, a recovery-steam discharge line (L 13) that supplies recovery steam discharged from the reclaimer to a bottom portion side of the absorbent regenerator, and a heating unit that heats an inside of the reclaimer. a branch line (L 10) that draws a part of the lean solution as lean drawn liquid, a reclaimer that takes in and reserves the lean drawn liquid, an alkaline-agent supply unit that supplies an alkaline agent into the reclaimer via an alkaline supply line (L 11), a reflux-water supply line (L 12) that supplies the reflux water into the reclaimer, a recovery-steam discharge line (L 13) that supplies recovery steam discharged from the reclaimer to a bottom portion side of the absorbent regenerator, and a heating unit that heats an inside of the reclaimer.