Aiming at the problem of high-speed water impacts formed during the water drawing of amphibious aircraft water tanks, the high-speed water impact load characteristics was studied. Firstly, a water impact experiment method based on adjusting the air pressure in the cavity is proposed. By adjusting the air pressure in the water storage container to change the water impact speed, the high-speed water flow impact experimental research is carried out. Then, based on ABAQUS CEL numerical simulation method, the initial velocity of water flow is preset, and the finite element model of high-speed water flow impact is established. The effects of water velocity and the distance between the end of water pipe and flat plate on the impact pressure was analyzed. The results show that the numerical simulation results are not much different from the experimental results, which verifies the accuracy of the model. The higher the water velocity is, the greater the impact pressure on the plate becomes, and the greater the distance between the end of the water pipe and the plate is, the smaller the impact pressure on the plate becomes.