Abstract: To meet the needs of transporting more oil in Ansai-Yan'an oil pipeline, the centrifugal pump sets used in the pumping stations along the line need to be modified. On the basis of analyzing the operation conditions of centrifugal pump sets and the possibility to increase the transportation pressure of the line, the pump sets modification program for Yanhewan station and Wangyao station have been determined and carried out. The statistical data have shown that the oil throughput after pump sets' modification is totally increased up to 801. 7 m³/d.that is.369.7 m³/d in Yanhewan pump station and 432 mVd in Wangyao pump station, which can meet the needs of oil transportation of the line. The calculation results show that the modification investment can be taken back within two months.