<p>Carbon dioxide enhanced oil recovery (CO₂-EOR) represents a critical technology for late-stage oilfield development and offers the highest economic returns among carbon capture, utilization, and storage (CCUS) solutions. Using operational data from Chinese oilfields, this study develops an innovative framework combining full life cycle assessment (LCA), techno-economic assessment (TEA), and system dynamics modeling to evaluate both the intrinsic viability of CO₂-EOR projects and the effectiveness of policy interventions. Our key findings reveal: (1) The Gate-to-Grave exhibits the highest carbon intensity in the life cycle, yet oilfield operations achieve net sequestration of 51.2% CO₂ per barrel of crude produced. (2) While all scenarios show negative net present value (NPV), optimization potential exists through development intensity.: Increasing operational scale reduces CO₂ feedstocks costs from $181.09 to $30.07 per barrel, demonstrating critical dependency on project design parameters. (3) Tax incentives outperform subsidies for profitability enhancement. Subsidy-driven scenarios yield limited revenues averaging $1 million/month, whereas tax rate adjustments and hybrid policies sustain revenues at $10 million/month levels.</p> Graphical Abstract <p></p>