CO2 geological storage into deep saline aquifers is one of the most promising methods for reducing anthropogenic CO2 emissions into the atmosphere. During the CO2 geological storage, many factors may affect the final success of actual storage projects, including storability, injectivity, and seal security. In order to investigate the impact of the desiccation phenomenon on the physical and chemical behaviors around the injection well, a series of numerical simulations were performed. Simulation results demonstrated that the geochemical reactions play an important role in the CO2 injection stage, especially the dissolution of easily soluble minerals, such as carbonates and sulfate.