Abstract: By means of the unit calculation method of evaporating volume for LNG receiving station, the re-condensation technological process of LNG receiving station is divided into 11 primary technology units such as tank evaporation, pipeline decalescence, tank flash vaporization, atmospheric pressure change, working of pump, etc.. Evaporating volume in each technology unit is calculated based on the first-period design scheme of Zhuhai LNG Receiving Station. Through comparing the computational results of evaporating volume in each technology unit, it could be concluded that evaporating volume produced in unloading displacement unit and returning LNG ship unit are more than that of other units, and both of them are closely related to the LNG ship's size, which are the key parameters to calculate the evaporating volume. Atmospheric pressure change is also an important parameter, so the climate factors should adequately be considered in the design. This method makes the factors considered in design of LNG receiving station more perfect, and all equipments and pipes related to evaporating volume in the station could be selected on basis of computational results for a single unit or combination units. Therefore, the design is more flexible and effective.