In view of the analysis and calculation of the water layout dimensions of harbor basin and channel,the PIANC specification proposes that in the conceptual design stage,the water layout dimension should be calculated rapidly by using formulas according to the natural condition,the basic parameter of ship and the influence of surrounding berth.In the detailed design stage,the simulation test should be used to simulate the actual working condition and accurately determine the channel layout and dimension.Taking the LNG terminal project in Southeast Asia as an example,this paper compares the formula of PIANC specification with the calculation of water layout dimension by simulation test.The results show that the simulation test can simulate the ship’s trajectory under different working conditions more accurately and truly than the formula calculation.The achievements can provide references for the similar projects.