Aiming at the problem that the small cut suction dredger“Junjiang” has short mud pipeline,high speed and high load when the diesel engine operates at rated speed in the construction of the project,we analyze the matching characteristics of mud pump and standard pipeline when conveying clean water,and the matching characteristics of mud pump and short mud discharge pipeline when conveying mud,adopt the measures of modifying the working conditions of the mud pump and the pipeline respectively to reach the working point of the match between the mud pump and the pipeline,and analyze the application effect.The results show that adjusting the speed of dredge pump and using small diameter impeller can make full use of the performance of diesel engine and dredge pump,and ensure the overall economic benefits of the project.