CO2-EGR technology, as a critical element within the framework of CCUS (CO2 capture, utilization, and storage), is recognized for its substantial potential in accomplishing the dual objectives of reducing carbon emissions and augmenting natural gas production. The mechanisms through which CO2 enhances natural gas recovery and storage are comprehensively outlined in this study, along with an examination of the associated potential and evaluation methodologies.Key findings indicate that CO2 improves natural gas recovery rates through mechanisms such as physical property differences, competitive adsorption, screening displacement, continuous convection displacement, restoration of gas reservoir pressure, and inhibition of water invasion. Additionally, the sealing mechanisms of CO2 in gas reservoirs encompass structural sealing, residual gas sealing, dissolution sealing, and mineralization sealing.The evaluation methods for CO2-enhanced natural gas recovery rates include numerical simulation, theoretical analysis, and physical experiments. Similarly, methods for assessing CO2 storage in gas reservoirs involve the effective volume method, material balance method, numerical simulation, and theoretical evaluation.While the potential of CO2 to enhance natural gas recovery is established, and preliminary evaluation methods are outlined, current applicability remains limited. Further refinement is deemed essential, particularly in consideration of the geological characteristics of natural gas reservoirs in China, to enhance the accuracy of storage assessments. Continuous research efforts are acknowledged as imperative to broaden the scope of application and optimize evaluation methodologies within this field.