The relationship model between the topography of the sea area and the layout scheme of the multi-beam survey line is established. The coverage width and overlap ratio of survey line are important indexes to measure the quality of survey line layout scheme. The calculation model of 2D and 3D sea area coverage width and overlap ratio is established by the analytical geometry method, and the basic method of measuring survey line layout scheme is obtained. At the same time, combining the survey line layout scheme with the optimization problem, the multi-objective planning model is established for the rectangular slope sea area and a real sea area to be measured respectively. The corresponding algorithm is designed to solve the model, and the optimal survey line layout scheme of the rectangular slope sea area and a feasible layout method of a real sea area to be measured are obtained. It is of reference significance to the practical multi-beam line layout problem.