The brine resource in the Qianjiang depression in Jianghan basin is rich in the brine resource because alternating deposits of gypsum mudstone, mudstone as well as sandstone of Qianjiang Formation form the potential sites for CO₂ geological storage. The purpose of this study is to investigate the physical and chemical responses under the condition of high salinity. The results show that the CO₂ dissolved in brine and sequestered in minerals decline significantly as a result of directly injecting CO₂ into the brine with high salinity, which may affect the storage safety.