Abstract: Provided is a carbon dioxide recovery system including: an absorption tower; a regeneration tower that takes in an absorbing solution that has absorbed carbon dioxide at the absorption tower, and separates the carbon dioxide from the absorbing solution using regenerated steam to regenerate the absorbing solution; first supply piping that supplies the absorbing solution regenerated in the regeneration tower to the absorption tower; a reclaimer that takes in part of the absorbing solution regenerated in the regeneration tower to remove degraded material and supplies the absorbing solution from which the degraded material has been removed to the regeneration tower or the first supply piping; an in-line viscometer that measures a viscosity of the absorbing solution flowing through the first supply piping; and a controller that controls an amount of the absorbing solution processed by the reclaimer based on the viscosity measured by the in-line viscometer.