For high-density cities, it is necessary for city managers to achieve precise regulation of carbon emissions and sequestration. For reference, taking Dongguan as example, this study proposed a complex framework to identify weak areas of urban land use carbon metabolism in high-density city. On the basic of defining the urban land use carbon metabolism units, LEAP, Markove-PLUS, and LANDIS model were applied to spatialize land use carbon emissions and carbon sequestration. Finally, the weak areas of urban land use carbon metabolism were clearly indicated through overlapping the spatial pattern of land use carbon emissions and sequestration. Accordingly, carbon emissions limit regions can be delimited, and its carbon emissions are recommended to be metabolize through connecting the limit regions to green spaces with various ecological corridors. The results will serve as a foundation to plan and control carbon emissions in high-density cities that are similar to Dongguan in international communities.