A carbon dioxide recovery system is configured to separate carbon dioxide from gas containing the carbon dioxide via an electrochemical reaction and includes an electrochemical cell including a working electrode and a counter electrode. The working electrode includes a CO2 adsorbent. The CO2 adsorbent is configured to, when a first voltage is applied between the working electrode and the counter electrode, take in electrons flowing from the counter electrode to the working electrode and adsorb the carbon dioxide by a Coulomb force of the electrons without bonding to the carbon dioxide by sharing an electron orbital with the carbon dioxide. The CO2 adsorbent is configured to, when a second voltage different from the first voltage is applied between the working electrode and the counter electrode, discharge the electrons from the working electrode to the counter electrode and desorb the carbon dioxide.