Aiming at the problem of shaft torque and power test of cutter suction dredger,field test and mud pump performance test are carried out,and a test device for shaft torque and shaft power test of cutter suction dredger is introduced.The performance parameters of mud pump at 850,900,950 and 1 000 r/min are obtained by using the method of measuring the power of ship strain gauge shaft,and the instantaneous and average pump shaft torque of diesel engine at 945 r/min and 18 throttle scale are calculated.It is concluded that:under the condition of constant flow rate,the higher the speed of pump is,the higher the lift and the higher the power is;when the flow rate is between 1 and 1.51 m3/s,the water powers of mud pump are very close at four rotational speeds；with the increase of flow rate,the higher the speed is,the higher the water power of pump is.