During the operation of propylene compressor unit in the ethylene plant of SINOPEC Shanghai Petrochemical Co., Ltd., the bearing bush temperature at the governor side of steam turbine remained high and fluctuated frequently. After analyzing the operation of bearing bush and the quality of lubricating oil, some corresponding measures were taken. Without shutting down the compressor unit, a certain proportion of the five groups of base oil was added into the oil tank to solve the high bearing bush temperature problem of steam turbine and improve the reliability of long-term operation of key compressor units.