The CO2 flooding in high temperature and salinity reservoirs of Zhongyuan oilfield is a new approach to improve the recovery when the reservoirs are at the late high water-cut period after water flooding.Application of foam sealing channeling in those reservoirs is an effective method.Aiming at the problem of severe gas channeling in test field,a system of CO2 foam system with heat resistance and tolerance to salt is developed.The system temperature-resistant reaches 100 ℃,salt-tolerant reaches 25×104 mg/L,Ca2+and Mg2+resistance up to 5×103 mg/L.A new understanding,the pressure is greater,foaming ability is stronger,is obtained through CO2 foam experiment in high temperature and high pressure.The CO2 foam phase change experiments show that the foaming ability and stability of supercritical CO2 foam are significantly higher than the gas CO2 foam and the maximum stabilizing time reaches 3 144.3 min.The CO2 foam system has been used in 16 wells in Zhongyuan oilfield and Yaoyingtai oilfield.The gas injection pressure rises by an average of 1-3 MPa and the success rate of operation is 100%.All wells get good seal channeling effects.The technology will provide a support for gas channeling control during CO2 flooding in high temperature and salinity reservoirs of Zhongyuan oilfield and also will provide references for similar reservoirs home and abroad.