In response to the vibration and noise issues caused by flow pulsation of axial piston pumps used in a certain type of ship, we used the RNG turbulence model and UDF dynamic grid technology in Fluent to simulate the reciprocating motion process of hydraulic oil under high-speed rotation. We obtained the trend of flow rate changes in the oil outlet chamber and studied the effects of rotational speed and outlet pressure on flow pulsation rate, in order to combine operating parameters with lower flow pulsation. The results show that the flow rate in the oil outlet chamber oscillates periodically, and the flow pulsation rate decreases as the speed decreases and the outlet pressure increases; When the outlet pressure is 18.5MPa and 31.5MPa, the flow pulsation rate at 1000r/min is reduced by 12.2% and 17.0% compared to 1800r/min. When the outlet pressure is 25MPa, the flow pulsation rate increases first and then decreases with the increase of speed. The paper provides strong support for vibration reduction and noise reduction of ship plunger pumps.