In this paper, an environmentally benign beta?cyclodextrin modified by maleic anhydride (MAH?β?CD) was prepared. A surfactant MJD230 was synthesized with CO₂ response through the electrostatic interaction between polyether diamine(Jeffamine D?230)and cyclodextrin modified by maleic anhydride under mild conditions. It effectively reduced the surface tension of aqueous solutions and aided the formation of a stable O/W emulsion. It shows switchability by bubbling CO₂, so that can be used repeatedly under the regulation of CO₂. The structure was characterized by FT-IR. The synthesis conditions of MJD230 were optimized via the viscosity reduction rate and emulsion particle size, and the viscosity reduction performance and stability were also investigated. Under the condition of mass fraction of 0.5% and oil-water volume ratio of 3:7, the viscosity reduction rate of MJD230 heavy oil can reach 99.19%. The reversible changes of pH and conductivity were used to prove the CO₂ responsiveness and repeatability of MJD230 solution. This provides the feasibility of a new enhanced heavy oil recovery technology combining surfactant flooding and CO₂ capture.