A carbon dioxide separation and recovery system includes: an adsorption reactor, which adsorbs, by an adsorbent, carbon dioxide contained in a to-be-treated gas, discharges the to-be-treated gas from which the carbon dioxide has been removed, and discharges the adsorbent that has adsorbed the carbon dioxide; a desorption reactor, which receives the adsorbent discharged from the adsorption reactor, condenses desorbing steam on the adsorbent to cause carbon dioxide to desorb from the adsorbent, and then discharges the adsorbent; and an adsorbent dryer, which receives the adsorbent discharged from the desorption reactor, dries the adsorbent until a water content ratio thereof becomes a predetermined value greater than or equal to a water content ratio limit by causing, with use of a drying gas, condensation water contained in the adsorbent to evaporate as steam, and then discharges the adsorbent.