Gaining carbon neutrality by 2060 and achieving carbon peaking by 2030 will involve formidable challenges for China in the future. In order for the government to effectively implement carbon emission reduction policies, it will be critical to comprehend the spatial patterns of carbon stocks in terrestrial ecosystems (LULCs) in the context of the region’s future development. In this study, we proposed LULC models for the Lhasa River Basin in Tibet from 2020 to 2040 under three distinct development scenarios. With the exception of the 2040 BAU scenario, the study’s findings indicate that carbon stocks in the future in the Lhasa River Basin will increase significantly in comparison to 2020. Furthermore, the overall carbon stocks in the basin will decrease significantly in the aforementioned development scenarios of 2040 and 2030. We ought to closely monitor the alterations in carbon stock and landscape composition that arise in the Lhasa River Basin as a result of the expansion of croplands. In the Lhasa River Basin, the degrees of variation in the spatial patterns of carbon stock are the least pronounced under all three scenarios, with the ELP scenario being particularly noteworthy.