Abstract: It is necessary to cool natural gas to about -162℃ during the liquefaction process. In order to avoid freezing plugging of the equipment and pipelines during the cryogenic liquefaction process, the acidic components of natural gas should be removed deeply. The key process technology of feed gas pretreatment unit for LNG plant, which includes desulfurization and decarbonization is mainly introduced. The characteristics and technical advantages of CT8-23 activated MDEA solvent and CT8-25 solvent, which can deeply remove the H₂S, CO₂ and organic sulfur, are described. Both of the solvents have been developed independently by Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company. Compared to similar foreign solvents Sulfinol-D, the results show that CT8-25 solvent can removal H₂S, CO₂ deeply to reach the requirements. When the absorption pressure is 2 MPa, the plate number of absorber is 13, and the removal rate of organic sulfur is 28% higher than Sulfinol-D.