In order to examine the performance of axial-flow water jet pump of a river trimaran, the bench test of scale model test pump is conducted. The external characteristic curve of real-scale water jet pump is obtained with a structured grid discrete calculation domain. The calculation value of Computational Fluid Dynamics (CFD) consistent with the test situation is obtained by the dimensionless similar conversion. The power and lift of test pump are measured under the condition that all the flow valves are open and the rotary speeds are not equal and under the condition that the flows are different and the rotary speeds are equal. On the basis of power loss analysis, the test measurement values are compared with the CFD calculation values. The results show that: they are of better agreement at 1 130～1 760 r/min, and the maximum error is 7.6%; the lift characteristic curve trends are of better consistency under the condition that the rotary speeds are equal.