Abstract: In order to make rational use of the resources of the South China Sea and its coastal ports, the design of cruise lines in the South China Sea is studied from the angle of the attraction and reliability of the routes. A mixed linear programming model is built and the algorithm for solving the model is developed to decide the ports to call and the order of visiting, the sailing speed of each segment of the trip and the time slot of the ship staying at each port on the principle of maximizing the attraction while keeping costs minimum. The model is verified with actual data. The sensitivity analysis is conducted against the number of lines and the number of calling ports.