Abstract: In order to study the energy consumption of large LNG plant, systematic analysis on the energy consumption situation were conducted and reasonable energy saving measures were proposed. Combined with GB/T 50441-2007 Energy Consumption Calculation Standard for Design of Petrochemical Industry, This paper conducted accounting on data from continuous operation of a large LNG plant, followed by scientific analysis with analytic hierarchy process (AHP), which finally led to energy-saving measures. The study results showed that electricity was the main energy source for the factory and reducing electricity consumption was the key measure for energy saving in the same processing scale. Unit energy consumption would decrease with the increasing of the daily processing load. Thus, energy saving was satisfactory at high processing load, and exhibited best at full capacity. Therefore, obtaining sufficient natural gas supply, maintaining smooth sales channels, achieving high load production could keep the operation cost of unit product at relatively low level.