The invention discloses a CO2 cyclic steam stimulation process, and belongs to the technical field of oilfield production process. The CO2 cyclic steam stimulation process comprises an installation shaft part and an installation ground blowout prevention part. The shaft part is composed of an oil pipe, a hollow rod and a metal screw pump. The ground blowout prevention part is composed of a screw pump driving device, a sucker rod blowout preventer and an oil production wellhead. The wellhead sealing can be guaranteed by the process, and the production can be resumed directly without operation after CO2 injection.