This paper introduces the BOG (Boil Off Gas) properties of LNG,and the BOG calculation method under different conditions,as well as two BOG processing techniques,direct compression technique and re-condensation technique.Two processing techniques are compared quantitatively with Bernoulli Equation and checking computations with examples are made.The results show that under same working conditions,the re-condensation technique can save energy compared to direct compression technique,and the greater the BOG p...