A carbon dioxide recovery system includes: an adsorber configured to adsorb and desorb carbon dioxide; a supply channel through which supply gas passes; a storage section configured to store carbon dioxide desorbed from the adsorber; and a gas supply section supplying carbon dioxide stored in the storage section to the adsorber. The carbon dioxide recovery system is operated in an adsorption mode, a desorption mode or in a desorption preparation mode. In the adsorption mode, the adsorber adsorbs CO2 contained in the supply gas supplied through the supply channel. In the desorption mode, the adsorber desorbs the adsorbed CO2, and the storage section stores CO2 desorbed from the adsorber. In the desorption preparation mode, the gas supply section supplies CO2 stored in the storage section to the adsorber during a time from an end of the adsorption mode to a start of the desorption mode.