To reasonably control the investment, the dredging ship types should be reasonably selected according to the project construction conditions. Based on the cutter suction dredger, according to the current dredging quota, this paper analyzes the composition and influencing factors of dredging price. By analyzing the price curve of different dredging ship types at different blowing distances, the changing trend of unit price is obtained and the economic ship types with the same blowing distances are found out. The economic and applicable dredging project scope of large and medium-sized cutter suction dredgers is summarized. The results show that when the blowing distance is the same, the large cutter suction dredger has obvious cost advantage and is more suitable for long distance blowing and filling. When the amount of dredging is small, the cost advantage of small and medium-sized cutter suction dredger is obvious. When the amount of dredging is more than 2 million m3, the cost advantage of large dredger is obvious. When the transport distance is far, it is better to choose grab dredger than rake suction dredger.