Reducing CO2 emission and lowering the concentration of greenhouse gases in the atmosphere has quickly become one of the most urgent environmental issues. While a variety of technologies and methods have been developed, the separation of CO2 from gas streams is still a critical issue. Apart from establishing new techniques, the exploration of membrane materials with high separation performance and low capital cost are of paramount importance. Functionalized polymers hold great potential as membrane materials in gas separation. In this paper, the research progress in functionalized polymers membrane materials for membrane-based high CO2 permselectivities separations that are directly related to CO2 capture were reviewed.