To　study　the　pressure　pulsations　induced　by　quasi-steady　cavitation　in　a　centrifugal　pump,　the　pressure　pulsations　at　the　pump　inlet　and　outlet　were　experimentally　investigated　with　the　development　of　cavitation.　Moreover,　the　internal　flow　characteristics　in　the　pump　during　the　process　were　numerically　determined.　The　numerical　simulation　results　agreed　well　with　the　results　obtained　from　the　experimental　test,　verifying　the　accuracy　of　the　numerical　simulation.　Furthermore,　the　cavitation-induced　pump　inlet　and　outlet　pressure　pulsations　of　the　centrifugal　pump　were　analyzed　by　wavelet　analysis　and　fast　Fourier　transform,　and　the　cavitation　incipient　point　and　occurrence　of　the　unstable　cavitation　point　were　obtained.　The　results　of　both　wavelet　analysis　and　fast　Fourier　transform　show　that　in　the　quasi-steady　cavitation　stage　of　the　centrifugal　pump　at　the　design　flow　rate,　the　pump　inlet　and　outlet　pressure　pulsations　are　significantly　increased　at　twice　the　axial　frequency,　while　the　other　axial　frequency　components　are　weak　and　the　internal　flow　is　stable.　With　the　development　of　cavitation　in　the　pump,　the　pump　inlet　and　outlet　pressure　pulsations　at　the　axial　frequency　and　its　multiples　afford　some　obvious　broadband　pulsations.　To　investigate　the　mechanism　of　quasi-steady　cavitation-induced　pressure　pulsation　in　the　centrifugal　pump,　the　dynamic　mode　decomposition　was　used　for　internal　flow　field　analysis.　The　results　show　that　different　inflow　states　lead　to　obvious　differences　in　the　internal　flow　and　unsteady　flow　structures.　There　are　complex　pressure　pulsation　characteristics　dominated　by　different　frequencies　in　the　centrifugal　pump.　Blade　passing　frequency　plays　an　important　role　in　the　entire　flow　field,　and　its　mechanism　has　been　analyzed.　This　research　will　provide　experimental　and　theoretical　support　for　quasi-steady　cavitation　recognition　and　help　researchers　improve　the　operation　stability　of　the　centrifugal　pump.