The work aims to avoid the poor quality of the pole piece drying due to the uneven distribution of the jet pressure during the drying process, because the oven jet nozzle has an important influence on the uniformity and consistency of the lithium battery pole piece drying. The air fluid domain between the jet nozzle and the pole piece was modeled by the SolidWorks software and the numerical simulation of warm air fluid field was calculated by the k-ε turbulence equation. The design of the jet nozzle structure was optimized according to the fluid simulation results and the experiment was carried out to verify and perfect the numerical simulation. The uniformity of pressure distribution between pole piece and air nozzle after numerical simulation optimization was greatly improved. The pressure difference obtained from simulation at the same test position was reduced from 20 Pa to 8 Pa, while the pressure difference obtained from the experiment was decreased to 11 Pa from 21 Pa. Within the error tolerance, the experimental results were basically consistent with the simulation results. The optimized jet nozzle has improved the pressure distribution, and numerical simulation research has important guiding significance for the optimal design of the jet nozzle structure.