Abstract: With the explosive growth of natural gas demands in China, the exporting pipelines of LNG terminals get longer and longer and correspondingly the outbound pressures also get higher and higher continuously, which requires more strictly on the performance of compressors and high-pressure pumps. In this paper, the Qingdao LNG terminal was taken as an example. In view of the change of its exporting pressure, it was proposed to transform its 4 high-pressure pumps by adding four-stage impellers. Then, the performance change of the exporting high-pressure pumps after the transformation and its influences on the process operation of the LNG terminal were analyzed. Finally, the change trends of the head coefficient, shaft power and efficiency of transformed high-pressure pumps with the increase of flow rate were tested on site. It is indicated that after high-pressure pumps are added with impellers, their head coefficient, shaft power, efficiency and electric current increase significantly. The operating parameters of 3 high-pressure pumps can satisfy the on-site actual demands of the LNG terminal, and the outbound pressure of the rest one is significantly low even under the same test condition. In this instance, the gasifier, the HIPPS system, the high pressure of exporting pipeline and the interlock value shall be increased correspondingly. In addition, leakage occurs frequently at the connection flanges in the high pressure zones of the LNG terminal, so it is necessary to enhance the inspection frequency and strength. When high-pressure pumps at the LNG terminal are different in performance, the pumps with similar performance shall be selected as far as possible in the process of operation. The research results can be used as the reference for the localized design and manufacture of high-pressure pump.