Land-use change is a crucial driver for achieving a sustainable future. However, the uncertainties of socioeconomic development could lead to different changes in the future land-use patterns. Using a spatial downscaling framework, this study aims to explore possible land-use patterns that can help achieve sustainable development in the Guangdong–Hong Kong–Macao Greater Bay Area, China (the Greater Bay Area). The framework combines the global Shared Socioeconomic Pathways (SSPs) scenarios with local land planning policies to model land-use changes. First, the Land Change Modeler was used to analyze the land-use changes from 2000 to 2010 and build transition potential submodels each of which demonstrates transition potential of different land-use classes. Second, future projections were made for the “business-as-usual” scenario and five localized SSP scenarios that were downscaled from global scenarios and modified based on the local land planning policy. Hong Kong was considered a typical case in the Greater Bay Area that could be used to demonstrate the application of the projected land-use maps by comparing the biocapacity and ecological footprint and estimating the carbon emissions associated with land use. The results of the future projections of land use made under six future scenarios indicated that there is a significant expansion in the urban area under all the scenarios, with varying degrees of decrease in cropland and forest among the different scenarios. Moreover, a land-use change also led to the change in local biocapacity and carbon emissions. Our analysis indicated that in achieving sustainable development not only urban area and cropland should be involved for consideration but should also cover the balance between all land-use classes, and three policy implications were proposed based on our findings.