A system based on virtual instrument was set up to test and analyze the pressure pulsation in centrifugal pump. It had adjustable sampling time length and frequency which can avoid the disadvantages of data loss and redundancy caused by fixed sampling parameters. A signal preprocessing toolkit compiled by LabVIEW was set up, which can anti the aliasing of the signal by use of the low pass filter, decrease the noise in the concerned frequency by the wavelet de-noising and efficiently reduce the error caused by test system. Meanwhile, the signal’s frequency characteristic could be analyzed in this system automatic, and the detail of the frequency characteristic could be captured by zoom FFT. All of the toolkits could be used as an automatic real-time system. The feasibility of this system has already been evaluated in a centrifugal pump system, and it is testified that this system can realize and analyze the pressure pulsation automatically.