<p>Under the Paris Agreement, each party is obliged to reduce greenhouse gas emissions based on its nationally determined contribution target. The status of greenhouse gas emissions is summarized by the National Greenhouse Gases Inventory Report (NIR). This report has some uncertainties. Inverse model and online coupled regional chemistry-meteorology model can be used to supplement NIR. In this study, the annual CO₂ emissions of South Korea estimated using surface CO₂ flux data from CarbonTracker, Copernicus Atmosphere Monitoring Service (CAMS), and the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) were compared with the annual CO₂ emissions of the NIR over 10-year period (2009–2018). To compare CO₂ fluxes from models with CO₂ emissions of the NIR, a method to convert CO₂ fluxes from the models to CO₂ emissions was devised. In South Korea, net CO₂ emissions of the NIR were greater than those estimated from the model results. CarbonTracker, CAMS, and WRF-Chem provided net CO₂ emission estimates and spatiotemporal CO₂ emission information suitable for comparing with the NIR CO₂ emissions. Meanwhile, land use, land use change, and forestry (LULUCF) sector CO₂ emissions were more comparable to the biospheric CO₂ emissions of the regional WRF-Chem than those of global inverse models (i.e., CarbonTracker and CAMS). This implies that the high-resolution regional model may provide more detailed spatiotemporal CO₂ emission information and its tendency due to the application of the more detailed land use and vegetation information to the model. The CO₂ emission information from the models is expected to be used for evaluating CO₂ emissions of the NIR and supporting CO₂ emission reduction policymaking.</p>