Abstract: By analyzing statistic data in several years of a combined station in Shengli Oil Field, testing various usable equipment on - the - spot, analyzing and calculating by utilizing relative knowledge concerning thermodynamics and heat transfer, find out the reason of big increasing in energy consumption in oil field's high water - cut period, mainly including following aspects : 1) unreasonable dehydrating process of original heating crude oil; 2) lower heat efficiency of heater; 3) large amount of heat loss resulting from uninsulation of the primary settling tank; 4) lower operation efficiency of crude oil out-transfer pump and dehydrating pump systems. Based on these, take energy saving and consumption cut - down measures for improving the original dehydrating process, insulating settling tank, using variable frequency and variable speed unit on oil - water pump to achieve the objective of energy saving and consumption cut-down.