According to the problem of more selection for boil-off gas processing system in LNG receiving terminals,the production of boil-off Gas under different working conditions is studied and calculated.The means of the combination for numerical calculation and theoretical research is used to analyze the effects of boil-off gas treatment capacity and the re-condenser pressure on energy consumption for boil-off gas treatment.On the above basis, the way of adding the heat exchanger is put forward, which reduces the energy consumption of boil-off gas treatment.The results show that the average energy consumption of boil-off gas treatment is increasing with the increase of boil-off gas treatment, tending to be stable. The re-condenser pressure has little effect on the average energy consumption,and there exists an optimal pressure value to minimize the average energy consumption.The calculation results of average energy consumption can provide a basis for the selection of boil-off gas processing system for new LNG receiving terminals.