Abstract: RPM saturation logging technology is one of the main technologies used in high water cut oil field to confirm residual oil saturation,increase oil production and dig oil production potential,as well as determinate the flooded degree.RPM residual oil saturation logging technique has been used in many oil fields in west of South China Sea,being the main technique to confirm residual oil saturation,supervise the flooding state of oil layers and oil-water production performance,and seek for potential oil producing position.This technology is very significant for making oil field development and adjustment scheme,increasing oil production and digging the production potential as well as enhanced oil recovery.