Abstract:Aiming at the research status and challenges of CO2 in the field of unconventional oil and gas stimulation, 12 application mechanisms of CO2 in fracturing, flooding and storage were summarized. Research status and technical demands at home and abroad in CO2 dry fracturing, CO2 foam fracturing, CO2 hybrid fracturing and CO2 flooding in recent years were analyzed. The future research focus of CO2 in the field of unconventional oil and gas stimulation is prospected.