Carbon capture and storage (CCS) is proposed as an effective way to reduce anthropogenic carbon dioxide (CO2) from the combustion of fossil fuels, in which CO2 capture or separation is an important step. Meanwhile, CO2 separation is also needed in biofuel production, for example, biogas upgrading to obtain biomethane or biosyngas purification to get syngas for producing biofuels. Many technologies have been developed for CO2 capture, while there still remains a need to develop new technologies. Ionic liquids (ILs) have been considered as “green” solvents and developed as liquid absorbents for CO2 capture; and deep eutectic solvents (DESs) as a new class of ILs or IL analogues show advantages on cost, environmental impact, and synthesis. In this chapter, the properties of DESs related to CO2 capture, such as gas solubility, viscosity, molar heat capacity, and gas absorption/desorption rate, are summarized and discussed. On the basis of the properties of DESs, the screening and evaluation of DESs for CO2 separation as well as the contribution of DESs to CO2 conversion are further discussed. In summary, the research work is still limited and more research needs to be carried out.