The work aims to explore the fluidization characteristics of wheat particles in tank and extraction pipe under different pressure during pneumatic conveying by warehouse pump, so as to obtain the optimal operating pressure. Solidworks was used to establish a simple three-dimensional model of the equal proportion transmission device. The simulation software Fluent was used to carry out numerical simulation of three different conveying pressure of 0.25, 0.3 and 0.35 MPa, and the data were post-processed by CFD-POST. When the air inlet pressure was 0.35 MPa, the material was transported firstly, which took 10 s. The pressure of the three parts from the inlet to the outlet of the extraction pipe was reduced by 97.1%, 96.8% and 98.1%, respectively. When the inlet pressure was 0.3 MPa, the pressure reduction was the smallest and the energy utilization was the highest. The higher the conveying pressure, the faster the conveying speed and the more the pressure drop. Considering economy and efficiency, the optimal inlet pressure is 0.3 MPa.