With the rapid development of dredging technology,the direct excavation of large-scale weathered rock by large dredgers becomes the main means of construction.Taking the “Electricity-Tianniu” series cutter suction dredger as an example，through a series of measures,such as rational selection of cutter head and cutter tooth,reduction of cutter tooth wear and softening rock,the productivity of ships is effectively improved and construction cost is reduced.Comparing with the traditional reef blasting and reef clearing construction technology,the cutter suction dredger excavation of weathered rock has the advantages of high construction efficiency and low cost.