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In order to study the characteristics of pressure pulsation in the impeller of submersible tubular pump, three pressure monitoring points were set up near the leading edge, middle and trailing edge of the impeller using a dynamic pressure sensor to measure the pressure pulsation under multiple working conditions. The test results showed that the blade frequency and the blade frequency multiple were the main frequencies of the pressure pulsation in the blade area under different flow conditions. Under the large flow conditions, the main frequency at the leading edge and trailing edge of the blade was twice of the blade frequency, the middle of the blade was the blade frequency, and the main frequency of each monitoring point was the blade frequency under other conditions. The influence of cavitation on the pressure pulsation of the leading edge of the blade was more complicated. Under the large flow condition, the main frequency of the critical cavitation was changed from twice of the blade frequency to one time of the blade frequency, and the amplitude of the main frequency was decreased significantly when the deep cavitation reached. Under the design flow condition, the cavitation made the harmonic frequency rise, and the frequency domain distribution was wider. Under the small flow condition, the main frequency amplitude showed an upward trend with the development of cavitation. The amplitude of the dominant frequency in the middle and trailing edge of the blade showed an increasing trend with the development of cavitation. Under the same flow conditions, the pressure pulsation intensity was generally decreased from the middle, trailing edge to the leading edge of the blade, and the pressure pulsation intensity of each monitoring point in the impeller was generally decreased with the increase of flow rate.