Abstract: We've analyzed and summarized the literatures about soil carbon in desertification area of China and found that there were two major issues on soil carbon in desertification area in China for historical and practical reasons. First，lack of enough real evidence and no appropriate method to use. On the other hand, the study on soil carbon in Qinghai Tibet Plateau and the Karst rocky desertification area in Southwest of China, which plays an important role in maintaining the sustainable development of China, were especially deficient. So, scholars could not answer the follow key scientific questions: in China, how was the size of the soil carbon sources and sinks in desertification area? How were they distribution and variation? Therefore, it was important for us to carry out basic research work in these fields. Firstly, it should strengthen collecting the basic data about soil carbon cycle of desert ecosystem. Second, pay more attention on the computational method of balance of payments about carbon stock of desert ecosystem. Thirdly, strengthen the empirical research on source and sink in desertification area of China. Finally, strengthen the basic research on soil carbon balance for those areas such as Qinghai Tibet Plateau and the southern Karst rocky desertification area, which plays a key role in the sustainable development of China. In order to fully, systematically estimate and evaluate the regional carbon source and sink size, distribution and change. So we could finally offer the basis for how to deal with the global climate change.