Considering actual mounting dimension of each pipe section, the steady and unsteady total flow field was calculated based on the excellent hydraulic model of axial flow pump. Fluid domain was discretized with structured mesh and analyzed with standard turbulence model. Pressure fluctuation values of impeller inlet, impeller outlet, middle of the guide vane and guide vane outlet were monitored. It turned out that prediction results were in good agreement with the experimental results. Radial distribution of pressure fluctuation for axial flow pump at different rotation speeds was investigated, and the results showed that the distribution of RMS along the radius also changed when the rotation speed varied. In terms of frequency domain chart, at the inlet of impeller, large amplitude of sub-harmonic emerged in the middle of the passage and near the hub; while at the guide vane outlet, amplitude of sub-harmonic of the monitor point in the middle of passage was relative higher and amplitude of sub-harmonic was relative lower near the hub and passage outer edge.