Abstract: For a crude oil stabilization unit, there exists a common phenomenon of higher water cut in unstable crude oil. which results in an abnormal running of the unit, and even the hydrocarbon black or flooding tower accidents. Therefore, technical improvement on the unit is necessary. By means of the hydrocarbon process software, simulation study is carried out on light hydrocarbon output atdifferent temperatures, water of dehydration volume and variation of heat flow. It is considered that operating condition of the crude oil stabilization unit and water of dehydration volume can be controlled at optimized state when outlet temperature of the heater is kept at 220℃.