Abstract: LNG storage tank is the most costly core facilities at LNG terminal. It is essential to reasonably estimate the tank capacity and quantity by static empirical formula in the early design stage. The LNG storage tank quantity and capacity should be calculated according to the local conditions, and the calculation methods vary for different design companies. In this paper, three static calculation methods commonly used in China and abroad are selected for specific design cases. The results show that, for the LNG terminal with relatively even delivery and not for peak shaving or for large LNG terminal with tanks added in late stage, the calculation method of a French design company is reasonable; for the LNG terminal which faces a volatile gas consumption market and plays the role for peak shaving, the calculation method of a Japanese design company and micro dynamic calculation are reasonable. Finally, considering the shortcomings of such three methods, an optimized formula is given, and applicable calculation methods are recommended for different types of terminals.