Based on the long-term monitoring data of Yanqi Basin, which is an important county along the Silk Road, 800 soil samples were collected during our study from the selected area to conduct soil organic carbon (SOC) determinations in the laboratory. By using the BCCC-CSM1.1 climate model from the Coupled Model Intercom parison Project Phase 5 (CMIP5), we expanded our work to research the change in the spatial distribution of the soil organic carbon density and organic carbon storage in the oasis area under climate change conditions. The results showed that:(1) The DNDC model better simulated the SOC content and dynamic change in the study area, the correlation coefficient was greater than 0.96, and the root mean square error (RMSE) between simulated and observed values was between 0.48% and 13.08%. The analog value was significantly correlated with the measured value. (2) The SOC content among different soils was significantly different. The growth trend of SOC content over the past five years was in the order silty loam > loam > sandy loam. (3) In 2017, the total SOC storage in the farmland of Yanqi County was 0.44 Tg C. In simulations of 30 years in the future, under the corresponding agricultural measures, the SOC density in the 0-20 cm soil layer in the study area exhibited a significant increasing trend. The SOC content per unit area was increased by -7%-29% and the new carbon fixation amount was 3.708×10⁸ t-1.978×10⁹ t, which could obtain an increase of -5%-48%. The unified management of farmland in the oasis areas will have an important impact on the effects of SOC fixation.