Sediment ecological dredging is an important measure to reduce endogenous pollutants，control black and odorous water bodies，and improve water quality. However，traditional dredging tools will cause the spread of sediment pollution sources and secondary pollution，which will affect the dredging effect. The CCCC Tianjin Dredging Co.，Ltd. has developed a new type of ecological dredging equipment，the working principle of the machine and the dredging capacity such as production capacity，traverse speed and mud suction concentration are theoretically analyzed. Using CFD simulation technology to analyze the hydrodynamic characteristics of the tool under different working conditions，it is found that the use of screw cutting and conveying can obtain a higher concentration of mud，and a smaller pitch parameter helps to achieve more mud suction. thus confirming that the designed machine has good dredging performance.