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The trend toward large and high speed centrifugal pump brings a great challenge for the safe and stable operation of centrifugal pumps. And fluid force induced vibration of centrifugal pumps is increased significantly. In order to reveal the fluid force induced vibration characteristic of centrifugal pumps, a single-blade centrifugal pump was used as the test pump. Based on the pump performance experiment, two vertically arranged eddy current displacement sensors were used to measure the transient displacement of impeller wear ring when pumping air and water. Time history and frequency spectrum of the displacement of the wear ring and locus of the wear ring displacement were obtained. Fluid force induced vibration characteristics of the centrifugal pump at different flow rates were obtained by using Huake hydraulic machinery tester based on the key phase information of the Hall sensor. The experimental results showed that the time history and frequency spectrum of the displacement of centrifugal pump were similar in both pumping air and water. Waveforms were periodically repeated distortion sinusoids and the dominant frequency was the rotational frequency of impeller. Locus of the wear ring displacement was distorted oval, and there was a mutation when pumping water. Fluid force induced locus of the wear ring displacement under different flow conditions were also distorted oval. And there was a mutation between 210° and 300°, the maximum appeared at around 130°. Fluid force induced vibration was significantly increased at the small flow rates, corresponding to the pump efficiency was significantly reduced, and it became weak at the design flow rate and large flow rates, corresponding to the higher efficiency of the pump. The research result provided a reference for the stable operation of centrifugal pumps and on-line fault diagnosis.