In Binzhou port 30 000 ton waterway project，soil has fine grain,and is dense and extrahard .There were some problem when CSD dredged the soil，which were that the cutter motor current fluctuated,and it was easy to hob when the cutter rotates in the same direction as the movement direction，and the shifing anchor might drag,and the productivity was low.To solve the above problems,we compared and analysed the cutter type,and adjusted excavation footage,and optimized the construction of key parameters,and found the pipeline additional resistance.Fluctuation amplitude of the cutter motor current was decreased.The frequency of hobbing and dragging was reduced.The productivity increased by about 15%.The construction costs was saved,while the time limit for the project was shortened .